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Sample records for apneic oxygenation combined

  1. [Apneic oxygenation].

    Science.gov (United States)

    Alekseev, A V; Vyzhigina, M A; Parshin, V D; Fedorov, D S

    2013-01-01

    Recent technological advances in thoracic and tracheal surgery make the anaesthesiologist use different respiratory techniques during the operation. Apneic oxygenation is a one of alternative techniques. This method is relatively easy in use, does not require special expensive equipment and is the only possible technique in several clinical situations when other respiratory methods are undesirable or cannot be used. However there is no enough information about apneic oxygenation in Russian. This article reviews publications about apneic oxygenation. The review deals with experiments on diffusion respiration in animals, physiological changes during apneic oxygenation in man and defines clinical cases when apneic oxygenation can be used.

  2. Apneic oxygenation combined with extracorporeal arteriovenous carbon dioxide removal provides sufficient gas exchange in experimental lung injury

    DEFF Research Database (Denmark)

    Nielsen, Niels Dalsgaard; Kjærgaard, Benedict; Nielsen, Jakob Koefoed

    injury was induced by repeated lung lavage. Thereafter the tracheal tube was, after a lung recruitment maneuver, connected to 20 cmH2O continuous positive airway pressure (FiO2 = 1.0) for oxygenation of the blood. A pumpless membrane lung (Interventional Lung Assist, NovaLung, Germany) was connected......Background and aim of study We hypothesized that continuous high airway pressure without ventilatory movements (apneic oxygenation), using an open lung approach, combined with extracorporeal, pumpless, arterio-venous, carbon dioxide (CO2) removal would provide adequate gas exchange in acute lung...... injury. The aim of this study was to test this hypothesis in a lung injury model using pigs of human adult size, to mimic the O2 consumption and the CO2 production of adult patients.   Materials and methods In eight anesthetized, tracheally intubated and mechanically ventilated pigs (85-95 kg), lung...

  3. Apneic oxygenation for elimination of respiratory motion artefact in an intubated patient undergoing helical chest computed tomography angiography.

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    Ioannis Pneumatikos

    2008-10-01

    Full Text Available Respiratory motion artifact in intubated and mechanically ventilated patients often reduces the quality of helical computed tomography pulmonary angiography (CTPA. Apneic oxygenation is a well established intra-operative technique that allows adequate oxygenation for short periods (up to 10 min in sedated and paralyzed patients. We describe the use of the apneic oxygenation for elimination of respiratory motion artefact in an intubated patient undergoing helical chest computed tomography angiography.

  4. Association of apneic oxygenation with decreased desaturation rates during rapid sequence intubation by a Chinese emergency medicine service.

    Science.gov (United States)

    Mao, Yong; Qin, Zong-He

    2015-01-01

    Rapid and safe airway management has always been of paramount importance in successful management of critically ill and injured patients in the emergency department. The achievement rate of emergency medicine inhabitants in airway management improved enhanced essentially subsequent to finishing anaesthesiology turn. There was a slightly higher rate of quick sequence intubation in the postapneic oxygenation groups (preapneic oxygenation 6.4%; postapneic oxygenation 9.1%). The majority of patients intubated in both groups were men (preapneic oxygenation 72.3%; postapneic oxygenation 63.5%). A higher percentage of patients in the preapneic oxygenation group had a Cormack-Lehane grade III or worse view (23.2% versus 11.8%). Anaesthesiology turns should be considered as an essential component of emergency medicine training programs. A collateral curriculum of this nature should also focus on the acquisition of skills in airway management.

  5. Association of apneic oxygenation with decreased desaturation rates during rapid sequence intubation by a Chinese emergency medicine service

    OpenAIRE

    Mao, Yong; Qin, Zong-He

    2015-01-01

    Rapid and safe airway management has always been of paramount importance in successful management of critically ill and injured patients in the emergency department. The achievement rate of emergency medicine inhabitants in airway management improved enhanced essentially subsequent to finishing anaesthesiology turn. There was a slightly higher rate of quick sequence intubation in the postapneic oxygenation groups (preapneic oxygenation 6.4%; postapneic oxygenation 9.1%). The majority of patie...

  6. EEG Suppression Associated with Apneic Episodes in a Neonate

    Directory of Open Access Journals (Sweden)

    Evonne Low

    2012-01-01

    Full Text Available We describe the EEG findings from an ex-preterm neonate at term equivalent age who presented with intermittent but prolonged apneic episodes which were presumed to be seizures. A total of 8 apneic episodes were captured (duration 23–376 seconds during EEG monitoring. The baseline EEG activity was appropriate for corrected gestational age and no electrographic seizure activity was recorded. The average baseline heart rate was 168 beats per minute (bpm and the baseline oxygen saturation level was in the mid-nineties. Periods of complete EEG suppression lasting 68 and 179 seconds, respectively, were recorded during 2 of these 8 apneic episodes. Both episodes were accompanied by bradycardia less than 70 bpm and oxygen saturation levels of less than 20%. Short but severe episodes of apnea can cause complete EEG suppression in the neonate.

  7. Cardiorespiratory responses and reduced apneic time to cold-water face immersion after high intensity exercise.

    Science.gov (United States)

    Konstantinidou, Sylvia; Soultanakis, Helen

    2016-01-01

    Apnea after exercise may evoke a neurally mediated conflict that may affect apneic time and create a cardiovascular strain. The physiological responses, induced by apnea with face immersion in cold water (10 °C), after a 3-min exercise bout, at 85% of VO2max,were examined in 10 swimmers. A pre-selected 40-s apnea, completed after rest (AAR), could not be met after exercise (AAE), and was terminated with an agonal gasp reflex, and a reduction of apneic time, by 75%. Bradycardia was evident with immersion after both, 40-s of AAR and after AAE (Pexercise without apnea was not equally elevated. The activation of neurally opposing functions as those elicited by the diving reflex after high intensity exercise may create an autonomic conflict possibly related to oxygen-conserving reflexes stimulated by the trigeminal nerve, and those elicited by exercise.

  8. Skin blood flow changes during apneic spells in preterm infants

    NARCIS (Netherlands)

    Suichies, H.E.; Aarnoudse, J.G.; Okken, A.; Jentink, H.W.; Mul, de F.F.M.; Greve, J.

    1989-01-01

    Changes in skin blood flow during apneic spells were determined in 18 preterm infants using a diode laser Doppler flow meter without light conducting fibres. Heart rate, nasal air flow, impedance pneumography, skin and incubator temperature and laser Doppler skin blood flow were recorded simultaneou

  9. Temporary diazepam responsive apneic attacks and congenital myasthenic syndrome.

    Science.gov (United States)

    Yis, Uluç; Kurul, Semra Hiz; Oztura, Ibrahim; Ozden, Omer; Akinci, Gülçin; Dirik, Eray

    2009-07-01

    Congenital myasthenic syndromes are a genetically and phenotypically heterogeneous group of hereditary disorders affecting neuromuscular junction. Mutations in the gene encoding choline acetyltransferase cause presynaptic defects. The missense mutation I336T has been identified in Turkish population, and most of the cases carrying this mutation present with exercise-induced fatigability and ptosis. Although apneic attacks occur in these cases during febrile illness in childhood, the number of reported respiratory distress episodes during infancy is scarce. Another important feature of these cases is that response to esterase inhibitors is satisfactory. We present a case of congenital myasthenic syndrome with I336T choline acetyltransferase mutation who presented with numerous attacks of respiratory distress in the infancy period. Interestingly, the patient had myopathic findings on electromyography and diazepam decreased severity of apneic attacks. There was also no improvement with esterase inhibitors.

  10. Sensitization by pulmonary reactive oxygen species of rat vagal lung C-fibers: the roles of the TRPV1, TRPA1, and P2X receptors.

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    Ting Ruan

    Full Text Available Sensitization of vagal lung C-fibers (VLCFs induced by mediators contributes to the pathogenesis of airway hypersensitivity, which is characterized by exaggerated sensory and reflex responses to stimulants. Reactive oxygen species (ROS are mediators produced during airway inflammation. However, the role of ROS in VLCF-mediated airway hypersensitivity has remained elusive. Here, we report that inhalation of aerosolized 0.05% H2O2 for 90 s potentiated apneic responses to intravenous capsaicin (a TRPV1 receptor agonist, α,β-methylene-ATP (a P2X receptor agonist, and phenylbiguanide (a 5-HT3 receptor agonist in anesthetized rats. The apneic responses to these three stimulants were abolished by vagatomy or by perivagal capsaicin treatment, a procedure that blocks the neural conduction of VLCFs. The potentiating effect of H2O2 on the apneic responses to these VLCF stimulants was prevented by catalase (an enzyme that degrades H2O2 and by dimethylthiourea (a hydroxyl radical scavenger. The potentiating effect of H2O2 on the apneic responses to capsaicin was attenuated by HC-030031 (a TRPA1 receptor antagonist and by iso-pyridoxalphosphate-6-azophenyl-2',5'-disulphonate (a P2X receptor antagonist. The potentiating effect of H2O2 on the apneic responses to α,β-methylene-ATP was reduced by capsazepine (a TRPV1 receptor antagonist, and by HC-030031. The potentiating effect of H2O2 on the apneic responses to phenylbiguanide was totally abolished when all three antagonists were combined. Consistently, our electrophysiological studies revealed that airway delivery of aerosolized 0.05% H2O2 for 90 s potentiated the VLCF responses to intravenous capsaicin, α,β-methylene-ATP, and phenylbiguanide. The potentiating effect of H2O2 on the VLCF responses to phenylbiguanide was totally prevented when all antagonists were combined. Inhalation of 0.05% H2O2 indeed increased the level of ROS in the lungs. These results suggest that 1 increased lung ROS sensitizes

  11. [A boy with nystagmus, refractory dystonia and apneic attack due to alternating hemiplegia of childhood].

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    Shiota, Naoki; Shimono, Masayuki; Tomioka, Shiho; Takano, Kenichi; Kato, Ayako; Kawakami, Akihiro; Ishizuka, Takehiro

    2007-07-01

    We herein report the findings of a 2-year-6-month-old boy, who had been experiencing monocular pendular nystagmus, strabismus, and episodic eye deviation nystagmus, intractable dystonia and apneic attack which all began when he was 2 days of age. He underwent a complete blood count test, blood chemistry test, analysis of amino acids in the blood and urine, analysis of pyruvate/lactate in blood and cerebrospinal fluid, head computed tomography and magnetic resonance imaging and no abnormal results were identified. His attacks were resistant to multiple antiepileptic and dopaminergic drugs. He showed transient left and/or right hemiplegia after nystagmus, dystonia and/or apneic attacks at 8-months of age with retardation in intelligence. We diagnosed him to have alternating hemiplegia of childhood (AHC). We were unsure how to deal with his attacks after he was discharged from the hospital, however, resuscitation with the ambu bag by his mother at home and the intravenous infusion of diazepam or thiamylal at the hospital together was proven to be an effective method for treating his severe apneic attacks. The effect of diazepam and amantadine on these attacks was transient, however, the administration of flunarizine with amantadine resulted in an improvement in his attacks. We therefore consider the administration of flunarizine to be essential for the effective treatment of AHC in this case.

  12. Christine Angot or the Autofiction as Apneic Literature

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    Alexandru MATEI

    2013-01-01

    Full Text Available A new literary genre is theorised in the seventies in France, autofiction, which combines characteristics of autobiography (especially what is called the nominal pact, the fact the the first person narrative has the same name as the author’s and of fiction (especially what is called symbolic conversion, in that the facts are not entirely realistic. There are in fact two kinds of autofiction : one which emphasizes on fiction (for instance a novel called Truismes by Marie Darrieussecq and the other one whose interest resides on encoding the “author’s” voice. The last kind of autofiction, illustrated here by Christine Angot’s books published from early 90’s, has not been clearly defined by narratologists, because its definition requires a deeper commitment of scholars in social description that formalist literary studies are not able to give. The signification of this literature is not to be established by a post-romantic aesthetics, and one proof would be Christine Angot’s novel Inceste: a “her-story” told in direct speech, to which the reader listen more than he reads it. What is transmitted is more an emergency of talking underlining a forgotten force of literature: the “immediate” expression of a psyche, of a human energy. Is that literature or not? Is it “for real” or only a literary convention made to impress the reader and to suspend all “aesthetic judgment”?

  13. Heart rate variability in non-apneic snorers and controls before and after continuous positive airway pressure

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    Mateika Jason H

    2005-07-01

    Full Text Available Abstract Background We hypothesized that sympathetic nervous system activity (SNSA is increased and parasympathetic nervous system activity (PNSA is decreased during non-rapid eye movement (NREM sleep in non-apneic, otherwise healthy, snoring individuals compared to control. Moreover, we hypothesized that these alterations in snoring individuals would be more evident during non-snoring than snoring when compared to control. Methods To test these hypotheses, heart rate variability was used to measure PNSA and SNSA in 11 normotensive non-apneic snorers and 12 control subjects before and 7-days after adapting to nasal continuous positive airway pressure (nCPAP. Results Our results showed that SNSA was increased and PNSA was decreased in non-apneic snorers during NREM compared to control. However, these changes were only evident during the study in which snoring was eliminated with nCPAP. Conversely, during periods of snoring SNSA and PNSA were similar to measures obtained from the control group. Additionally, within the control group, SNSA and PNSA did not vary before and after nCPAP application. Conclusion Our findings suggest that long-lasting alterations in autonomic function may exist in snoring subjects that are otherwise healthy. Moreover, we speculate that because of competing inputs (i.e. inhibitory versus excitatory inputs to the autonomic nervous system during snoring, the full impact of snoring on autonomic function is most evident during non-snoring periods.

  14. Combined application of XANES and XPS to study oxygen species adsorbed on Ag foil

    CERN Document Server

    Bukhtiyarov, V I; Kaichev, V V; Knop-Gericke, A; Mayer, R W; Schloegl, R

    2001-01-01

    Adsorbed oxygen species realized in the course of ethylene epoxidation over polycrystalline silver have been characterized by X-ray absorption near the edge structure and X-ray photoelectron spectroscopy. Namely, the combined application of XANES and XPS in similar UHV conditions using the same sample allowed us to assign an XAS feature to the nucleophilic and electrophilic oxygen. This is of great significance, since these species are suggested to be included into the active center for ethylene epoxidation. The differences in the oxygen-silver bonding of these oxygen species are discussed.

  15. Hyperbaric oxygen therapy combined with Schwann cell transplantation promotes spinal cord injury recovery

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    Chuan-gang Peng

    2015-01-01

    Full Text Available Schwann cell transplantation and hyperbaric oxygen therapy each promote recovery from spinal cord injury, but it remains unclear whether their combination improves therapeutic results more than monotherapy. To investigate this, we used Schwann cell transplantation via the tail vein, hyperbaric oxygen therapy, or their combination, in rat models of spinal cord contusion injury. The combined treatment was more effective in improving hindlimb motor function than either treatment alone; injured spinal tissue showed a greater number of neurite-like structures in the injured spinal tissue, somatosensory and motor evoked potential latencies were notably shorter, and their amplitudes greater, after combination therapy than after monotherapy. These findings indicate that Schwann cell transplantation combined with hyperbaric oxygen therapy is more effective than either treatment alone in promoting the recovery of spinal cord in rats after injury.

  16. Effect of hyperbaric oxygen therapy combined with autologous platelet concentrate applied in rabbit fibula fraction healing

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    Paulo Cesar Fagundes Neves

    2013-09-01

    Full Text Available OBJECTIVES: The purpose is to study the effects of hyperbaric oxygen therapy and autologous platelet concentrates in healing the fibula bone of rabbits after induced fractures. METHODS: A total of 128 male New Zealand albino rabbits, between 6-8 months old, were subjected to a total osteotomy of the proximal portion of the right fibula. After surgery, the animals were divided into four groups (n = 32 each: control group, in which animals were subjected to osteotomy; autologous platelet concentrate group, in which animals were subjected to osteotomy and autologous platelet concentrate applied at the fracture site; hyperbaric oxygen group, in which animals were subjected to osteotomy and 9 consecutive daily hyperbaric oxygen therapy sessions; and autologous platelet concentrate and hyperbaric oxygen group, in which animals were subjected to osteotomy, autologous platelet concentrate applied at the fracture site, and 9 consecutive daily hyperbaric oxygen therapy sessions. Each group was divided into 4 subgroups according to a pre-determined euthanasia time points: 2, 4, 6, and 8 weeks postoperative. After euthanasia at a specific time point, the fibula containing the osseous callus was prepared histologically and stained with hematoxylin and eosin or picrosirius red. RESULTS: Autologous platelet concentrates and hyperbaric oxygen therapy, applied together or separately, increased the rate of bone healing compared with the control group. CONCLUSION: Hyperbaric oxygen therapy and autologous platelet concentrate combined increased the rate of bone healing in this experimental model.

  17. Combined effects of individual culture and atmospheric oxygen on preimplantation mouse embryos in vitro.

    Science.gov (United States)

    Kelley, Rebecca L; Gardner, David K

    2016-11-01

    Embryos are routinely cultured individually, although this can reduce blastocyst development. Culture in atmospheric (20%) oxygen is also common, despite multiple detrimental effects on embryos. Although frequently occurring together, the consequences of this combination are unknown. Mouse embryos were cultured individually or grouped, under physiological (5%) or atmospheric (20%) oxygen. Embryos were assessed by time-lapse and blastocyst cell allocation. Compared with the control group (5% oxygen group culture), 5-cell cleavage (t5) was delayed in 5% oxygen individual culture and 20% oxygen group culture (59.91 ± 0.23, 60.70 ± 0.29, 63.06 ± 0.32 h post-HCG respectively, P culture were delayed earlier (3-cell cleavage), and at t5 cleaved later than embryos in other treatments (66.01 ± 0.40 h, P culture and 20% oxygen group culture (134.1 ± 3.4, 104.5 ± 3.2, 73.4 ± 2.2 cells, P culture (57.0 ± 2.8 cells, P culture and 20% oxygen is detrimental to embryo development.

  18. ACUPUNCTURE COMBINED WITH INHALATION OF OXYGEN FOR TREATMENT OF 60 CASES OF EXTENSIVE ANXIETY

    Institute of Scientific and Technical Information of China (English)

    DU Hong

    2005-01-01

    Objective: To observe the therapeutic effects and adverse effects of "channel-oxygen therapy" for extensive anxiety. Methods: Sixty cases of extensive anxiety patients were treated with "channel-oxygen therapy" once daily and continuously for 4 weeks. Neiguan(内关PC 6) and Zusanli(足三里ST 36) were needled in combination with nasal inhalation of oxygen, 30 min each session. The therapeutic effects were assessed by Hamilton Anxiety Scale (HAMA) and the adverse effects by Treatment Emergent Symptom Scale (TESS). Results: Of the 60 cases, 35 were cured, 13 improved and 12 were ineffective, with the effective rate being 80.0% and the cured rate 58.3%. No evident adverse effects were found. Conclusion: The "channel-oxygen therapy" is safe and effective for extensive anxiety.

  19. Hyperbaric oxygen combined with drug therapy in the treatment of acute cerebral infarction clinical analysis

    Institute of Scientific and Technical Information of China (English)

    Wen-Cui Lin; Kang Lin; Jing Wang; Shuai Li

    2015-01-01

    Objective:To explore the effects of hyperbaric oxygen combined with edaravone, salviae miltiorrhizae and ligustrazine and sodium ozagrel in the treatment of acute cerebral infarction clinical analysis.Methods: A total of 200 cases of acute cerebral infraction patients were randomly divided into observation group and control group. The control group was treated with edaravone, salvia miltiorrhizae and ligustrazine and sodium ozagrel; on the basis of treatment in control group, the observation group was combined with hyperbaric oxygen therapy. The neurological deficit scores were observed before and after treatment in patients of two groups, meanwhile the activities of daily living (ADL) and clinical effects were compared.Results: The total effective rate in observation group (92%) was significantly higher than control group (79%), the differences were statistically significant; the score of ADL in observation group after treatment was obviously higher than control group [(79.91±5.16)vs (61.62±5.60)], and the differences were statistically significant. The neurological deficit scores after treatment were obviously lower than the control group [(9.55±4.13)vs (15.46±4.92)], the differences were statistically significant.Conclusion: Hyperbaric oxygen combined with edaravone, salvia miltiorrhizae and ligustrazine and sodium ozagrel in the treatment of acute cerebral infarction can improve the symptoms of microcirculation and neurologic impairment, and improve the patient s quality of life.

  20. Quantitative measurement of neuronal degeneration in organotypic hippocampal cultures after combined oxygen/glucose deprivation.

    Science.gov (United States)

    Strasser, U; Fischer, G

    1995-04-01

    Organotypic hippocampal cultures were used to study cell degeneration during the recovery period after defined periods (30 and 60 min) of combined oxygen/glucose deprivation mimicking transient ischemic conditions. Staining with the fluorescent dye propidium iodide allowed detection of damaged cells. Fluorescence intensity was measured by an image analysis system and used to quantify cell damage at different time points during the recovery period (up to 22 h). At 30 min of oxygen/glucose deprivation cells in the CA1 area were relatively more sensitive compared to CA3 and dentate gyrus cells, with respect to the time course of degeneration and the percentage of affected cells. Expanding the oxygen/glucose deprivation period from 30 to 60 min drastically increased the percentage of cells dying in all hippocampal areas. Still, however, cells in CA1 degenerated faster compared to those in the CA3 area and dentate gyrus. A histological analysis of toluidine blue as well as MAP2-immunostained sections revealed that almost all neurons degenerated in all hippocampal areas following the 60-min deprivation period, whereas GFAP-stained astrocytes appeared to be unaffected. Therefore, neuronal degeneration could be quantified by taking the fluorescence intensity values 22 h after 60 min of oxygen/glucose deprivation as 100% neuronal damage. The possibility to quantify neuronal damage in organotypic cultures offers a useful tool for detailed studies on mechanisms of neuronal cell death in a cell culture system which is closer to in situ conditions than monolayer cell cultures.

  1. Effects of combined irradiation of 500 keV protons and atomic oxygen on polyimide films

    Science.gov (United States)

    Novikov, Lev; Chernik, Vladimir; Zhilyakov, Lev; Voronina, Ekaterina; Chirskaia, Natalia

    2016-07-01

    Polyimide films are widely used on the spacecraft surface as thermal control coating, films in different constuctions, etc. However, the space ionizing radiation of different types can alter the mechanical, optical and electrical properties of polyimide films. For example, it is well known that 20-100 keV proton irradiation causes breaking of chemical bonds and destruction of the surface layer in polyimide, deterioration of its optical properties, etc. In low-Earth orbits serious danger for polymeric materials is atomic oxygen of the upper atmosphere of the Earth, which is the main component in the range of heights of 200-800 km. Due to the orbital spacecraft velocity, the collision energy of oxygen atoms with the surface ( 5 eV) enhances their reactivity and opens additional pathways of their reaction with near-surface layers of materials. Hyperthermal oxygen atom flow causes erosion of the polyimide surface by breaking chemical bonds and forming of volatiles products (primarily, CO and CO _{2}), which leads to mass losses and degradation of material properties. Combined effect of protons and oxygen plasma is expected to give rise to synergistic effects enhancing the destruction of polyimide surface layers. This paper describes experimental investigation of polyimide films sequential irradiation with protons and oxygen plasma. The samples were irradiated by 500 keV protons at fluences of 10 ^{14}-10 ^{16} cm ^{-2} produced with SINP cascade generator KG-500 and 5-20 eV neutral oxygen atoms at fluence of 10 ^{20} cm ^{-2} generated by SINP magnetoplasmodynamics accelerator. The proton bombardment causes the decrease in optical transmission coefficient of samples, but their transmittance recovers partially after the exposure to oxygen plasma. The results of the comparative analysis of polyimide optical transmission spectra, Raman and XPS spectra obtained at different stages of the irradiation of samples, data on mass loss of samples due to erosion of the surface are

  2. Clinical experience with TENS and TENS combined with nitrous oxide-oxygen. Report of 371 patients.

    OpenAIRE

    Quarnstrom, F. C.; Milgrom, P.

    1989-01-01

    Transcutaneous electrical nerve stimulation (TENS) alone or TENS combined with nitrous oxide-oxygen (N2O) was administered for restorative dentistry without local anesthesia to 371 adult patients. A total of 55% of TENS alone and 84% of TENS/N2O visits were rated successful. A total of 53% of TENS alone and 82% of TENS/N2O patients reported slight or no pain. In multivariable analyses, pain reports were related to the anesthesia technique and patient fear and unrelated to sex, race, age, toot...

  3. Prenatal Nicotinic Exposure Upregulates Pulmonary C-fiber NK1R Expression to Prolong Pulmonary C-fiber-Mediated Apneic Response

    Science.gov (United States)

    Zhao, Lei; Zhuang, Jianguo; Zang, Na; Lin, Yong; Lee, Lu-Yuan; Xu, Fadi

    2015-01-01

    Prenatal nicotinic exposure (PNE) prolongs bronchopulmonary C-fiber (PCF)-mediated apneic response to intra-atrial bolus injection of capsaicin in rat pups. The relevant mechanisms remain unclear. Pulmonary substance P and adenosine and their receptors (neurokinin-A receptor, NK1R and ADA1 receptor, ADA1R) and transient receptor potential cation channel subfamily V member 1 (TRPV1) expressed on PCFs are critical for PCF sensitization and/or activation. Here, we compared substance P and adenosine in BALF and NK1R, ADA1R, and TRPV1 expression in the nodose/jugular (N/J) ganglia (vagal pulmonary C-neurons retrogradely labeled) between Ctrl and PNE pups. We found that PNE failed to change BALF substance P and adenosine content, but significantly upregulated both mRNA and protein TRPV1 and NK1R in the N/J ganglia and only NK1R mRNA in pulmonary C-neurons. To define the role of NK1R in the PNE-induced PCF sensitization, the apneic response to capsaicin (i.v.) without or with pretreatment of SR140333 (a peripheral and selective NK1R antagonist) was compared and the prolonged apnea by PNE significantly shortened by SR140333. To clarify if the PNE-evoked responses depended on action of nicotinic acetylcholine receptors (nAChRs), particularly α7nAChR, mecamylamine or methyllycaconitine (a general nAChRs or a selective α7nAChR antagonist) was administrated via another mini-pump over the PNE period. Mecamylamine or methyllycaconitine eliminated the PNE-evoked mRNA and protein responses. Our data suggest that PNE is able to elevate PCF NK1R expression via activation of nAChRs, especially α7nAChR, which likely contributes to sensitize PCFs and prolong the PCF-mediated apneic response to capsaicin. PMID:26524655

  4. [Evaluation of cerebral oxygenation in newborns with prematurity apnea: new frequency domain NIR oximeter].

    Science.gov (United States)

    Pratesi, S; Donzelli, G

    2000-01-01

    Near infrared spectroscopy (NIRS) is a non invasive, portable, safe technique for monitoring cerebral oxygenation and haemodynamics. A new frequency-domain tissue oximeter based on a multi-distance measurement protocol is presented. The effects of apneic episodes on cerebral and peripheral arterial oxygen saturation (SatO2) in preterm newborns, as monitored by NIRS and by pulse oximetry, are reported. The study population consist of 5 preterms (26 to 30 weeks of gestational age), in the second week of postnatal age, affected by apnea of prematurity. NIRS and pulse oximetric measurements were made contemporarily for a 40-minutes period for each infant. All monitorized apneic events were associated with bradicardia, and resolved spontaneously or after tactile stimulation. As results: a) there was always cerebral deoxygenation in association with apneic events, b) the mean SatO2 as measured by NIRS was slightly lower than the pulse oximeter readings, c) cerebral SatO2 decreased faster and the absolute value of the cerebral SaO2 decrease was greater than that measured peripherally (mean value of 27 versus 13%), d) increases of cerebral deoxyhemoglobin and total hemoglobin and a decrease of oxyhemoglobin were also observed. These preliminary results show that peripheral oxygen saturation measurements as measured by pulse oximetry could not always reflect brain oxygenation.

  5. Combination of positioning therapy and venovenous extracorporeal membrane oxygenation in ARDS patients.

    Science.gov (United States)

    Kredel, M; Bischof, L; Wurmb, T E; Roewer, N; Muellenbach, R M

    2014-03-01

    Positioning therapy may improve lung recruitment and oxygenation and is part of the standard care in severe acute respiratory distress syndrome (ARDS). Venovenous extracorporeal membrane oxygenation (vvECMO) is a rescue strategy that may ensure sufficient gas exchange in ARDS patients failing conventional therapy. The aim of this case series was to describe the feasibility and pitfalls of combining positioning therapy and vvECMO in patients with severe ARDS. A retrospective cohort of nine patients is described. The patients received 20 (15-86) hours (median, 25(th) and 75(th) percentile) of positioning therapy while being treated with vvECMO. The initial PaO2/FiO2 index was 64 (51-67) mmHg and the arterial carbon dioxide tension was 60 (50-71) mmHg. Positioning therapy included 135 degrees prone, prone positioning and continuous lateral rotational therapy. During the first three days, the oxygenation index improved from 47 (41-47) to 12 (11-14) cmH2O/mmHg. The lung compliance improved from 20 (17-28) to 42 (27-43) ml/cmH2O. Complications related to positioning therapy were facial oedema (n=9); complications related to vvECMO were entrance of air (n=1) and pump failure (n=1). However, investigation of root causes revealed no association with the positioning therapy and had no documented effect on the outcome. The reported cases suggest that positioning therapy can be performed safely in ARDS patients treated with vvECMO, providing appropriate precautions are in place and a very experienced team is present.

  6. Combined impact of water column oxygen and temperature on internal oxygen status and growth of Zostera marina seedlings and adult shoots

    DEFF Research Database (Denmark)

    Raun, Ane-Marie Løvendahl; Borum, Jens

    2013-01-01

    Eelgrass (Zostera marina L.) occasionally experiences severe die-offs during warm summer periods with variable water column oxygen partial pressures (pO). Eelgrass is known to be very intolerant to tissue anoxia with reduced growth and increasing mortality after ≤12h anoxia in the dark at tempera...... periods of unusually high temperatures expected in the future as a result of global warming. © 2013 Elsevier B.V.......Eelgrass (Zostera marina L.) occasionally experiences severe die-offs during warm summer periods with variable water column oxygen partial pressures (pO). Eelgrass is known to be very intolerant to tissue anoxia with reduced growth and increasing mortality after ≤12h anoxia in the dark...... at temperatures of ≥25°C. In the present study we experimentally examine the impact of combined water column oxygen and temperature on oxygen dynamics in leaf meristems of seedlings and adult shoots to better understand how stressful environmental conditions affect eelgrass oxygen dynamics and subsequent growth...

  7. Monitoring hemodynamics and oxygenation of the kidney in rats by a combined near-infrared spectroscopy and invasive probe approach

    Science.gov (United States)

    Grosenick, Dirk; Cantow, Kathleen; Arakelyan, Karen; Wabnitz, Heidrun; Flemming, Bert; Skalweit, Angela; Ladwig, Mechthild; Macdonald, Rainer; Niendorf, Thoralf; Seeliger, Erdmann

    2015-07-01

    We have developed a hybrid approach to investigate the dynamics of perfusion and oxygenation in the kidney of rats under pathophysiologically relevant conditions. Our approach combines near-infrared spectroscopy to quantify hemoglobin concentration and oxygen saturation in the renal cortex, and an invasive probe method for measuring total renal blood flow by an ultrasonic probe, perfusion by laser-Doppler fluxmetry, and tissue oxygen tension via fluorescence quenching. Hemoglobin concentration and oxygen saturation were determined from experimental data by a Monte Carlo model. The hybrid approach was applied to investigate and compare temporal changes during several types of interventions such as arterial and venous occlusions, as well as hyperoxia, hypoxia and hypercapnia induced by different mixtures of the inspired gas. The approach was also applied to study the effects of the x-ray contrast medium iodixanol on the kidney.

  8. A fascinating combination of Co, Ni and Al nanomaterial for oxygen evolution reaction

    Science.gov (United States)

    Khan, Sher Bahadar; Khan, Shahid Ali; Asiri, Abdullah M.

    2016-05-01

    Interesting combination of Co, Ni and Al have been assessed for oxygen evolution reaction (OER). Layered double hydroxide (LDH) nanosheets of NiCoAl, Co-Al oxide nanoparticles and Co-Ni oxide nanoparticles were prepared and studied for the first time as OER catalyst. Among all the subjected catalysts, the binary LDH comprise of NiCoAl showed comparatively high catalytic activity than Co-Al oxide nanoparticles and Co-Ni oxide nanoparticles. The Co-Al and Co-Ni oxide nanoparticles showed current densities of 34.6 and 24.5 mA cm-2, respectively at 1 V in 0.3 M KOH solution. However at the same conditions, NiCoAl-LDH showed comparatively low overpotential, high current density (40.8 mA cm-2) and lower Tafel slope. The low overpotential and high catalytic activity of NiCoAl-LDH stipulate the possibility to reduce the demand of precious, rare earth and expensive transition metal catalyst in electrochemical water splitting for OER.

  9. A fascinating combination of Co, Ni and Al nanomaterial for oxygen evolution reaction

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Sher Bahadar, E-mail: sbkhan@kau.edu.sa [Center of Excellence for Advanced Materials Research, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589 (Saudi Arabia); Chemistry Department, Faculty of Science, King Abdulaziz University, P. O. Box 80203, Jeddah, 21589 (Saudi Arabia); Khan, Shahid Ali; Asiri, Abdullah M. [Center of Excellence for Advanced Materials Research, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589 (Saudi Arabia); Chemistry Department, Faculty of Science, King Abdulaziz University, P. O. Box 80203, Jeddah, 21589 (Saudi Arabia)

    2016-05-01

    Graphical abstract: - Highlights: • Cobalt based nanomaterials. • Water splitting. • Low overpotential. • Plausible self-repair electrocatalyst. - Abstract: Interesting combination of Co, Ni and Al have been assessed for oxygen evolution reaction (OER). Layered double hydroxide (LDH) nanosheets of NiCoAl, Co-Al oxide nanoparticles and Co-Ni oxide nanoparticles were prepared and studied for the first time as OER catalyst. Among all the subjected catalysts, the binary LDH comprise of NiCoAl showed comparatively high catalytic activity than Co-Al oxide nanoparticles and Co-Ni oxide nanoparticles. The Co-Al and Co-Ni oxide nanoparticles showed current densities of 34.6 and 24.5 mA cm{sup −2}, respectively at 1 V in 0.3 M KOH solution. However at the same conditions, NiCoAl-LDH showed comparatively low overpotential, high current density (40.8 mA cm{sup −2}) and lower Tafel slope. The low overpotential and high catalytic activity of NiCoAl-LDH stipulate the possibility to reduce the demand of precious, rare earth and expensive transition metal catalyst in electrochemical water splitting for OER.

  10. Improvement of Surface Wettability and Hydrophilization of Poly-paraphenylene benzobisoxazole Fiber with Fibrillation Combined Oxygen Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Xiwen Wang

    2012-01-01

    Full Text Available A new surface modification method fibrillation combined with oxygen plasma treatment to improve the wettability and hydrophily of PBO fiber was studied in this paper. The surface chemical structure and morphology of PBO fiber were characterized by the methods of FTIR, XPS and SEM. The wettability and hydrophlic characters changes on the surface were evaluated by the dynamic contact angle system and image analysis. The results show that the increase surface roughness by fibrillation could improve the wettability. Fibrillation combined oxygen plasma treatment has a better effect than oxygen plasma treatment to improve the wettability and hdyrophlization of PBO fiber. The specific area of PBO fiber increased to 10.7 m2/g from 0.7 m2/g, contact angle decreased to 43.2° from 84.4° and WRV increased to 208.4% from 13.7%. The modified fibers have a good dispersion in water for hydrophilization improvement.

  11. Effects of temperature and irradiance on a benthic microalgal community: A combined two-dimensional oxygen and fluorescence imaging approach

    DEFF Research Database (Denmark)

    Hancke, Kasper; Sorrell, Brian Keith; Lund-Hansen, Lars Chresten

    2014-01-01

    The effects of temperature and light on both oxygen (O2) production and gross photosynthesis were resolved in a benthic microalgae community by combining two-dimensional (2D) imaging of O2 and variable chlorophyll a (Chl a) fluorescence. Images revealed a photosynthetically active community...

  12. Effect of growth hormone, hyperbaric oxygen and combined therapy on the gastric serosa

    Science.gov (United States)

    Adas, Gokhan; Adas, Mine; Arikan, Soykan; Sarvan, Ahu Kemik; Toklu, Akin Savas; Mert, Selva; Barut, Gul; Kamali, Sedat; Koc, Bora; Tutal, Firat

    2013-01-01

    AIM: To investigate the role of growth hormone (GH), hyperbaric oxygen therapy (HBOT) and combined therapy on the intestinal neomucosa formation of the gastric serosa. METHODS: Forty-eight male Wistar-albino rats, weighing 250-280 g, were used in this study. The rats were divided into four groups (n = 12): Group 1, control, gastric serosal patch; Group 2, gastric serosal patch + GH; Group 3, gastric serosal patch + HBOT; and Group 4, gastric serosal patch + GH + HBOT. Abdominal access was achieved through a midline incision, and after the 1-cm-long defect was created in the jejunum, a 1 cm × 1 cm patch of the gastric corpus was anastomosed to the jejunal defect. Venous blood samples were taken to determine the insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP-3) basal levels. HBOT was performed in Groups 3 and 4. In Groups 2 and 4, human GH was given subcutaneously at a dose of 2 mg per kg/d for 28 d, beginning on the operation day. All animals were sacrificed 60 d after surgery. The jejunal segment and the gastric anastomotic area were excised for histological examination. The inflammatory process, granulation, collagen deposition and fibroblast activity at the neomucosa formation were studied and scored. Additionally, the villus density, villus height, and crypt depth were counted and recorded. The measurements of villus height and crypt depth were calculated with an ocular micrometer. New vessel growth was determined by calculatingeach new vessel in a 1 mm2 area. RESULTS: In the histological comparison of groups, no significant differences were observed between the control group and Groups 2 and 3 with respect to epithelialization, granulation, fibroblastic activity and the inflammatory process, but significant differences were present between the control group and all others groups (Groups 2-4) with respect to angiogenesis (P < 0.01) and collagen deposition (P < 0.05, P < 0.01). Significant differences between the

  13. Atomic oxygen dynamics in an air dielectric barrier discharge: a combined diagnostic and modeling approach

    Science.gov (United States)

    Baldus, Sabrina; Schröder, Daniel; Bibinov, Nikita; Schulz-von der Gathen, Volker; Awakowicz, Peter

    2015-06-01

    Cold atmospheric pressure plasmas are a promising alternative therapy for treatment of chronic wounds, as they have already shown in clinical trials. In this study an air dielectric barrier discharge (DBD) developed for therapeutic use in dermatology is characterized with respect to the plasma produced reactive oxygen species, namely atomic oxygen and ozone, which are known to be of great importance to wound healing. To understand the plasma chemistry of the applied DBD, xenon-calibrated two-photon laser-induced fluorescence spectroscopy and optical absorption spectroscopy are applied. The measured spatial distributions are shown and compared to each other. A model of the afterglow chemistry based on optical emission spectroscopy is developed to cross-check the measurement results and obtain insight into the dynamics of the considered reactive oxygen species. The atomic oxygen density is found to be located mostly between the electrodes with a maximum density of {{n}\\text{O}}=6× {{10}16} cm-3 . Time resolved measurements reveal a constant atomic oxygen density between two high voltage pulses. The ozone is measured up to 3 mm outside the active plasma volume, reaching a maximum value of {{n}{{\\text{O}3}}}=3× {{10}16} cm-3 between the electrodes.

  14. Improvement of Surface Wettability and Hydrophilization of Poly-paraphenylene benzobisoxazole Fiber with Fibrillation Combined Oxygen Plasma Treatment

    OpenAIRE

    Xiwen Wang; Jian Hu,; Yun Liang

    2012-01-01

    A new surface modification method fibrillation combined with oxygen plasma treatment to improve the wettability and hydrophily of PBO fiber was studied in this paper. The surface chemical structure and morphology of PBO fiber were characterized by the methods of FTIR, XPS and SEM. The wettability and hydrophlic characters changes on the surface were evaluated by the dynamic contact angle system and image analysis. The results show that the increase surface roughness by fibrillation could impr...

  15. Investigation of Pinus mugo essential oil oxygenated fraction by combined use of gas chromatography and dry column chromatography.

    Science.gov (United States)

    A, M B; Coran, S A; Giannellini, V; Vincieri, F F; Moneti, G

    1981-09-01

    The oxygenated compounds of Pinus mugo Turra essential oil were investigated by a combination of GC and dry column chromatography (DCC) coordinated by GC data processing. The collected data resulted in a bar graph ("normalized" gas chromatogram) giving the RRT's and relative amounts of 68 components; 38 of them were identified by MS and IR. The described procedure may be used for essential oil analysis in general.

  16. Combined administration of hyperbaric oxygen and hydroxocobalamin improves cerebral metabolism after acute cyanide poisoning in rats

    DEFF Research Database (Denmark)

    Hansen, M B; Olsen, Niels Vidiendal; Hyldegaard, O

    2013-01-01

    Hyperbaric oxygen therapy (HBOT) or intravenous hydroxocobalamin (OHCob) both abolish cyanide (CN)-induced surges in interstitial brain lactate and glucose concentrations. HBOT has been shown to induce a delayed increase in whole blood CN concentrations, whereas OHCob may act as an intravascular CN...

  17. Cryogenic oxygen jet response to transverse acoustic excitation with the first transverse and the first combined longitudinal-transverse modes

    Science.gov (United States)

    Hardi, J. S.; Oschwald, M.

    2016-07-01

    The intact length of the dense oxygen core from an oxygen-hydrogen shear coaxial rocket injector was measured. The measurements were made in a rectangular rocket combustor with optical access and acoustic forcing. The combustor was operated at chamber pressures of 40 and 60 bar, with either ambient temperature or cryogenic hydrogen. The multielement injection spray is subjected to forced transverse gas oscillations of two different acoustic resonance modes; the first transverse (1T) mode at 4200 Hz and the first combined longitudinal-transverse (1L1T) at 5500 Hz. Intact core length is measured from high-speed shadowgraph imaging. The dependence of intact core length with increasing acoustic amplitude is compared for the two modes of excitation.

  18. Iron-oxygen interaction in silicon: A combined XBIC/XRF-EBIC-DLTS study of precipitation and complex building

    Energy Technology Data Exchange (ETDEWEB)

    Trushin, M., E-mail: trushmax@tu-cottbus.d [IHP/BTU Jointlab, Konrad-Wachsmann Allee 1, 03046 Cottbus (Germany); Vyvenko, O. [V.A.Fok Institute of Physics, St. Petersburg State University, Ulyanovskaya 1, 108594 St. Petersburg (Russian Federation); Seifert, W. [IHP/BTU Jointlab, Konrad-Wachsmann Allee 1, 03046 Cottbus (Germany); IHP microelectronics, Im Technologiepark 25, D-15236 Frankfurt (Oder) (Germany); Jia, G. [IHP/BTU Jointlab, Konrad-Wachsmann Allee 1, 03046 Cottbus (Germany); Kittler, M. [IHP/BTU Jointlab, Konrad-Wachsmann Allee 1, 03046 Cottbus (Germany); IHP microelectronics, Im Technologiepark 25, D-15236 Frankfurt (Oder) (Germany)

    2009-12-15

    Iron-oxygen interaction in the Czochralski-grown silicon (CZ-Si) giving rise to their final precipitated state was investigated by means of a combination of electrical and element-sensitive techniques. The samples studied were intentionally contaminated with iron at 1150 deg. C and then they were annealed at temperatures of 850 and 950 deg. C to stimulate precipitate formation. Fe-related defect levels in silicon band gap and spatial distributions of iron-related precipitates were monitored after each annealing step. It was found that FeB-pairs being the dominant defects in as-contaminated sample transformed completely to the stable FeO-related complexes that served as precursors for further iron-oxygen co-precipitation.

  19. Iron-oxygen interaction in silicon: A combined XBIC/XRF-EBIC-DLTS study of precipitation and complex building

    Science.gov (United States)

    Trushin, M.; Vyvenko, O.; Seifert, W.; Jia, G.; Kittler, M.

    2009-12-01

    Iron-oxygen interaction in the Czochralski-grown silicon (CZ-Si) giving rise to their final precipitated state was investigated by means of a combination of electrical and element-sensitive techniques. The samples studied were intentionally contaminated with iron at 1150 °C and then they were annealed at temperatures of 850 and 950 °C to stimulate precipitate formation. Fe-related defect levels in silicon band gap and spatial distributions of iron-related precipitates were monitored after each annealing step. It was found that FeB-pairs being the dominant defects in as-contaminated sample transformed completely to the stable FeO-related complexes that served as precursors for further iron-oxygen co-precipitation.

  20. Development Status for a Combined Solid Oxide Co-Electrolyzer and Carbon Formation Reactor System for Oxygen Regeneration

    Science.gov (United States)

    Green, Robert D.; Matter, Paul H.; Holt, Chris; Beachy, Michael; Gaydos, James; Farmer, Serene C.; Setlock, John

    2016-01-01

    A critical component in spacecraft life support loop closure is the removal of carbon dioxide (CO2, produced by the crew) from the cabin atmosphere and chemical reduction of this CO2 to recover the oxygen. In 2015, we initiated development of an oxygen recovery system for life support applications consisting of a solid oxide co-electrolyzer (SOCE) and a carbon formation reactor (CFR). The SOCE electrolyzes a combined stream of carbon dioxide (CO2) and water (H2O) gas mixtures to produce synthesis gas (e.g., CO and H2 gas) and pure dry oxygen as separate products. This SOCE is being developed from a NASA GRC solid oxide fuel cell and stack design originally developed for aeronautics long-duration power applications. The CFR, being developed by pHMatter LLC, takes the CO and H2 output from the SOCE, and converts it primarily to solid carbon (C(s)) and H2O and CO2. Although the solid carbon accumulates in the CFR, the innovative design allows easy removal of the carbon product, requiring minimal crew member (CM) time and low resupply mass (1.0 kg/year/CM) for replacement of the solid carbon catalyst, a significant improvement over previous Bosch reactor approaches. In this work, we will provide a status of our Phase I efforts in the development and testing of both the SOCE and CFR prototype units, along with an initial assessment of the combined SOCE-CFR system, including a mass and power projections, along with an estimate of the oxygen recovery rate.

  1. Monitoring cancer treatment response using photoacoustic and ultrasound spectral analysis in combination with oxygenation measurements (Conference Presentation)

    Science.gov (United States)

    Hysi, Eno; May, Jonathan P.; Wirtzfeld, Lauren; Undzys, Elijus; Li, Shyh-Dar; Kolios, Michael C.

    2016-03-01

    At clinically-relevant depths, the frequency content of photoacoustic signals encodes information about the size, concentration and spatial distribution of non-resolvable blood vessels. This study evaluates whether photoacoustics can detect cancer therapy-induced vascular perturbations. Photoacoustic/ultrasound (PA/US) spectral analysis was combined with functional, PA-based oxygenation and power Doppler (PD) perfusion estimates to assess treatment response. Co-registered, in-vivo US/PA/PD imaging of mice bearing breast cancer tumors was performed pre-treatment and 30m/2h/5h/24h/7d post-treatment (VevoLAZR, Fujifilm VisualSonics). Hyperthermia treatment (1h, 43C) was performed after systemic injections of doxorubicin-loaded thermosensitive liposomes (TSL, n=13) or free doxorubicin (DOX, n=11). Response was classified according to 2h, PA-based oxygenation drop and endpoint (>9d), caliper-based volume reduction. At all time-points/wavelengths (750/850nm), the spectral-slope (SS) was computed from the normalized US/PA power spectra using depth-matched reference phantoms. The percent-vascularity (PV) was estimated for the animal with the largest oxygenation-drop at 2h. TLS-treated responders decreased their PA-SS by 1.9x @750nm and 5.8x @850nm 30m post-treatment and remained constant for 24h; tumor oxygenation followed the same trend. Non-responding SS remained unchanged for 24h. The 750nm SS was 18.7x lower than 850nm suggesting the TSL is sensitive vessel oxygenation. Responder PV decreased 100% when the 30m oxygenation dropped 15% and increased 7x when the 7d oxygenation increased 20%. DOX-responders exhibited similar trends to TSL-responders although the 750nm PA-SS was 1.6x smaller and post-treatment PV was 50% higher. The US-SS remained unchanged until 7d post-treatment suggesting its sensitivity to tumor cell-death. These findings suggest that PA spectral analysis has potential in monitoring cancer treatment response.

  2. Sequence effects of combined resistance exercises with step choreography in the same session in women's oxygen uptake during and postexercise.

    Science.gov (United States)

    Vilaça-Alves, José; Regado, Ana; Marinho, Daniel; Neves, Eduardo Borba; Rosa, Claudio; Saavedra, Francisco; Reis, Victor M

    2016-07-11

    The combination of step choreography (SC) with resistance training exercises (RE) in the same session is common in class fitness rooms populated mainly by women to increase energy expenditure. The aim of this study was to evaluate the differences in the exercise oxygen uptake and postexercise between two different combinations of resistance training exercises and step choreography, regarding the order of execution. Thirteen active women (30·31 ± 4·42 years, 62·02 ± 5·37 kg, 162·65 ± 4·40 cm, 19·14 ± 3·29% body fat) performed two combinations: step choreography before resistance training, where resistance training was divided into two blocks of analysis (10 min each); and step choreography divided into three equal blocks (10 min for each block), before, in the middle and after resistance exercise. There were significant differences (Pchoreography in blocks, a significant (P = 0·001) decrease between blocks 2 and 3 in the step choreography before resistance exercise and a significant (Pchoreography and resistance exercises during the same exercise session is a good strategy to promote an elevation of women's oxygen uptake during and after an exercise session, independent of the sequence used.

  3. Percutaneous treatment of non-contained lumbar disc herniation by injection of oxygen-ozone combined with collagenase

    Energy Technology Data Exchange (ETDEWEB)

    Wu Zhiqun [Therapy Center of Pain, Division of Interventional Radiology, Tang Du Hospital, Fourth Military Medical University, Xian 710038 (China)], E-mail: zhiqunwu@yahoo.com; Wei Longxiao [Therapy Center of Pain, Division of Interventional Radiology, Tang Du Hospital, Fourth Military Medical University, Xian 710038 (China); Li Jun [Therapy Center of Pain, Division of Orthopedic Surgery, Tang Du Hospital, Fourth Military Medical University, Xian 710038 (China); Wang Yiqing; Ni Daihui [Therapy Center of Pain, Division of Interventional Radiology, Tang Du Hospital, Fourth Military Medical University, Xian 710038 (China); Yang Peng; Zhang Yuhai [Department of Biostatistics, Fourth Military Medical University, Xian 710032 (China)

    2009-12-15

    Purpose: To evaluate the therapeutic results of oxygen-ozone combined collagenase injection for the treatment of lumbar disc herniation compared to the surgery. And to explore the role of this minimally invasive treatment as an alternative to disc surgery. Materials and methods: Two groups of patients (n = 108) were treated with different ways respectively. Minimally invasive group of patients was treated with the injection of oxygen-ozone combined with collagenase into the lumbar disc or the epidural space; the other group was treated with traditional surgery. After the treatment, the patients were followed-up and the therapeutic effect was assessed at 2 weeks, 3 and 12 months by the modified Macnab criteria. Results: The success rate was 86.11% and 88.89% in minimally invasive group at 3 and 12 months respectively, while 92.59% and 95.37% in surgical group. There was no statistically significant difference between two groups at 3 and 12 months (P = 0.123, P = 0.08). However, the surgical group produced a statistically significant greater improvement for back pain and disability in the first few weeks (P = 0.0001). The success rate was 51.86% and 85.18% at 2 weeks in minimally invasive group and surgical group respectively. No serious complication occurred in this group. Conclusions: The combination of the oxygen-ozone with collagenase shows significant reductions in pain and improvements in function at 3 and 12 months, it can be considered as an option for the treatment of non-contained lumbar disc herniation instead of surgery.

  4. Quantifying the cerebral metabolic rate of oxygen by combining diffuse correlation spectroscopy and time-resolved near-infrared spectroscopy.

    Science.gov (United States)

    Verdecchia, Kyle; Diop, Mamadou; Lee, Ting-Yim; St Lawrence, Keith

    2013-02-01

    Preterm infants are highly susceptible to ischemic brain injury; consequently, continuous bedside monitoring to detect ischemia before irreversible damage occurs would improve patient outcome. In addition to monitoring cerebral blood flow (CBF), assessing the cerebral metabolic rate of oxygen (CMRO2) would be beneficial considering that metabolic thresholds can be used to evaluate tissue viability. The purpose of this study was to demonstrate that changes in absolute CMRO2 could be measured by combining diffuse correlation spectroscopy (DCS) with time-resolved near-infrared spectroscopy (TR-NIRS). Absolute CBF was determined using bolus-tracking TR-NIRS to calibrate the DCS measurements. Cerebral venous blood oxygenation (SvO2) was determined by multiwavelength TR-NIRS measurements, the accuracy of which was assessed by directly measuring the oxygenation of sagittal sinus blood. In eight newborn piglets, CMRO2 was manipulated by varying the anesthetics and by injecting sodium cyanide. No significant differences were found between the two sets of SvO2 measurements obtained by TR-NIRS or sagittal sinus blood samples and the corresponding CMRO2 measurements. Bland-Altman analysis showed a mean CMRO2 difference of 0.0268 ± 0.8340 mLO2/100 g/min between the two techniques over a range from 0.3 to 4 mL O2/100 g/min.

  5. Pulmonary functional MRI:an animal model study of oxygen-enhanced ventilation combined with Gd-DTPA-enhanced perfusion

    Institute of Scientific and Technical Information of China (English)

    杨健; 万明习; 郭佑民

    2004-01-01

    Background The assessment of regional pulmonary ventilation and perfusion is essential for the evaluation of a variety of lung disorders. Pulmonary ventilation MRI using inhaled oxygen as a contrast medium can be obtained with a clinical MR scanner, without additional equipment, and has been demonstrated to be a feasible means of assessing ventilation in animal models and some clinical patients. However, few studies have reported on MR ventilation-perfusion imaging. In this study, we evaluated the usefulness of oxygen-enhanced ventilation in combination with first-pass Gd-DTPA-enhanced perfusion MRI in a canine model of pulmonary embolism and airway obstruction.Methods Peripheral pulmonary embolisms were produced in eight dogs by intravenous injection of gelfoam strips at the pulmonary segmental arterial level, and airway obstructions were created in five of the dogs by inserting a self-designed balloon catheter into a secondary bronchus. Oxygen-enhanced MR ventilation images were produced by subtracting images from before and after inhalation of pure oxygen. Pulmonary perfusion MR images were acquired with a dynamic three-dimensional fast gradient-echo sequence. MR ventilation and perfusion images were read and contrasted with results from general examinations of pathological anatomy, ventilation-perfusion scintigraphy, and pulmonary angiography. Results Regions identified as having airway obstructions matched using both MR ventilation and perfusion imaging, but regions of pulmonary embolisms were mismatched. The area of airway obstruction defects was smaller using MR ventilation imagery than that using ventilation scintigraphy. Abnormal perfusion regions due to pulmonary embolisms were divided into defective regions and reduced regions based on the time course of signal intensity changes. In the diagnosis of pulmonary embolisms with the technique of ventilation and perfusion MRI, sensitivity and specificity were 75.0% and 98.1%, respectively, and the diagnostic

  6. A combined sensor for simultaneous high resolution 2-D imaging of oxygen and trace metals fluxes

    DEFF Research Database (Denmark)

    Stahl, Henrik; Warnken, Kent W.; Sochaczewski, Lukasz

    2012-01-01

    demonstrated localized mobilization of Ni, Cu, and Pb close to the burrow wall, where O-2 was elevated. The latter was also confirmed for Cu and Pb in natural sediments irrigated by the polychaete Hediste diversicolor. The sandwich sensor has great potential for investigating interrelations between O-2 d......A new sandwich sensor, consisting of an O-2 planar optode overlain by a thin (90 mu m) DGT layer is presented. This sensor can simultaneously resolve 2-D O-2 dynamics and trace metal fluxes in benthic substrates at a high spatial resolution. The DGT layer accumulates metals on a small particle size...... that the enhanced smearing and reduced response time of the O-2 signal associated with the additional DGT layer were marginal. To test sensor performance at realistic conditions, it was applied to an artificial burrow system consisting of permeable dialysis tubing flushed with oxygenated seawater. The measurements...

  7. Comparison between intrarticular injection of hyaluronic acid, oxygen ozone, and the combination of both in the treatment of knee osteoarthrosis.

    Science.gov (United States)

    Giombini, A; Menotti, F; Di Cesare, A; Giovannangeli, F; Rizzo, M; Moffa, S; Martinelli, F

    2016-01-01

    This study aimed to compare short-term clinical outcomes between intra-articular injection of hyaluronic acid (HA), oxygen ozone (O2O3), and the combination of both, in patients affected by osteoarthrosis (OA) of the knee. Seventy patients (age 45-75 years) with knee OA were randomized to intra-articular injections of HA (n=23), or O2O3 (n=23) or combined (n=24) one per week for 5 consecutive weeks. KOOS questionnaire and visual analog scale (VAS), before treatment (pre) at the end (post), and at 2 months after treatment ended (follow-up) were used as outcome measures. Analysis showed a significant effect (P < 0.05) of the conditions (pre, post and follow-up) in all parameters of the KOOS score and a significant effect (P < 0.05) of groups (HA, O2O3 and combined) for pain, symptoms, activities of daily living and quality of life. The combined group scores were higher compared to the HA and O2O3 groups, especially at follow-up. The combination of O2O3 and HA treatment led to a significantly better outcome especially at 2-month follow-up compared to HA and O2O3 given separately to patients affected by OA of the knee.

  8. Kinetics of oxygen reduction in perovskite cathodes for solid oxide fuel cells: A combined modeling and experimental approach

    Science.gov (United States)

    Miara, Lincoln James

    Solid oxide fuel cells (SOFCs) have the potential to replace conventional stationary power generation technologies; however, there are major obstacles to commercialization, the most problematic of which is poor cathode performance. Commercialization of SOFCs will follow when the mechanisms occurring at the cathode are more thoroughly understood and adapted for market use. The catalytic reduction of oxygen occurring in SOFC cathodes consists of many elementary steps such as gas phase diffusion, chemical and/or electrochemical reactions which lead to the adsorption and dissociation of molecular oxygen onto the cathode surface, mass transport of oxygen species along the surface and/or through the bulk of the cathode, and full reduction and incorporation of the oxygen at the cathode/electrolyte two or three phase boundary. Electrochemical impedance spectroscopy (EIS) is the main technique used to identify the occurrence of these different processes, but when this technique is used without an explicit model describing the kinetics it is difficult to unravel the interdependence of each of these processes. The purpose of this dissertation is to identify the heterogeneous reactions occurring at the cathode of an SOFC by combining experimental EIS results with mathematical models describing the time dependent behavior of the system. This analysis is performed on two different systems. In the first case, experimental EIS results from patterned half cells composed of Ca-doped lanthanum manganite (LCM)| yttria-doped ZrO2 (YSZ) are modeled to investigate the temperature and partial pressure of oxygen, pO2, dependence of oxygen adsorption/dissociation onto the LCM surface, surface diffusion of atomic oxygen, and electrochemical reduction and incorporation of the oxygen into the electrolyte in the vicinity of the triple phase boundary (TPB). This model determines the time-independent state-space equations from which the Faradaic admittance transfer function is obtained. The

  9. Umbilical cord-derived mesenchymal stem cell transplantation combined with hyperbaric oxygen treatment for repair of traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Hai-xiao Zhou; Zhi-gang Liu; Xiao-jiao Liu; Qian-xue Chen

    2016-01-01

    Transplantation of umbilical cord-derived mesenchymal stem cells (UC-MSCs) for repair of traumatic brain injury has been used in the clinic. Hyperbaric oxygen (HBO) treatment has long been widely used as an adjunctive therapy for treating traumatic brain injury. UC-MSC transplantation combined with HBO treatment is expected to yield better therapeutic effects on traumatic brain injury. In this study, we established rat models of severe traumatic brain injury by pressurized lfuid (2.5–3.0 atm impact force). The injured rats were then administered UC-MSC transplantationvia the tail vein in combination with HBO treatment. Compared with monotherapy, aquaporin 4 expression decreased in the injured rat brain, but growth-associated protein-43 expression, calaxon-like structures, and CM-Dil-positive cell number increased. Following combination therapy, however, rat cognitive and neurological function signiifcantly improved. UC-MSC transplantation combined with HBO therapyfor repair of traumatic brain injury shows better therapeutic effects than monotherapy and signiifcantly promotes recovery of neurological functions.

  10. Effect of resveratrol and beta-sitosterol in combination on reactive oxygen species and prostaglandin release by PC-3 cells.

    Science.gov (United States)

    Awad, Atif B; Burr, Andrew T; Fink, Carol S

    2005-03-01

    The objective of this project was to identify some possible mechanisms by which two common phytochemicals, resveratrol and beta-sitosterol, inhibit the growth of human prostate cancer PC-3 cells. These mechanisms include the effect of the phytochemicals on apoptosis, cell cycle progression, prostaglandin synthesis and the production of reactive oxygen species (ROS). Prostaglandins have been known to play a role in regulating cell growth and apoptosis. PC-3 cells were supplemented with 50 microM resveratrol or 16 microM beta-sitosterol alone or in combination for up to 5 days. Phytochemical supplementation resulted in inhibition in cell growth. beta-Sitosterol was more potent than resveratrol and the combination of the two resulted in greater inhibition than supplementation with either alone. Long-term supplementation with resveratrol or beta-sitosterol elevated basal prostaglandin release but beta-sitosterol was much more potent than resveratrol in this regard. beta-Sitosterol was more effective than resveratrol in inducing apoptosis and the combination had an intermediate effect after 1 day of supplementation. Cells supplemented with resveratrol were arrested at the G1 phase and at the G2/M phase in the case of beta-sitosterol while the combination resulted in cell arrest at the two phases of the cell cycle. beta-Sitosterol increased ROS production while resveratrol decreased ROS production. The combination of the two phytochemicals resulted in an intermediate level of ROS. The observed changes in prostaglandin levels and ROS production by these two phytochemicals may suggest their mediation in the growth inhibition. The reduction in ROS level and increase by resveratrol supplementation in PC-3 cells reflects the antioxidant properties of resveratrol. It was concluded that these phytochemicals may induce the inhibition of tumor growth by stimulating apoptosis and arresting cells at different locations in the cell cycle and the mechanism may involve alterations in

  11. Effect of ambient combinations of argon, oxygen, and hydrogen on the properties of DC magnetron sputtered indium tin oxide films

    Directory of Open Access Journals (Sweden)

    M. Marikkannan

    2015-01-01

    Full Text Available Sputtering has been well-developed industrially with singular ambient gases including neutral argon (Ar, oxygen (O2, hydrogen (H2 and nitrogen (N2 to enhance the electrical and optical performances of indium tin oxide (ITO films. Recent preliminary investigation into the use of combined ambient gases such as an Ar+O2+H2 ambient mixture, which was suitable for producing high-quality (low sheet resistance and high optical transmittance of ITO films. To build on this promising preliminary work and develop deeper insight into the effect of ambient atmospheres on ITO film growth, this study provides a more detailed investigation of the effects of ambient combinations of Ar, O2, H2 on sputtered ITO films. Thin films of ITO were deposited on glass substrates by DC magnetron sputtering using three different ambient combinations: Ar, Ar+O2 and Ar+O2+H2. The structural, electrical and optical properties of the three ambient sputtered ITO films were systematically characterized by X-ray diffraction (XRD, atomic force microscopy (AFM, scanning electron microscopy (SEM, Raman spectroscopy, four probe electrical conductivity and optical spectroscopy. The XRD and Raman studies confirmed the cubic indium oxide structure, which is polycrystalline at room temperature for all the samples. AFM shows the minimum surface roughness of 2.7 nm for Ar+O2+H2 sputtered thin film material. The thickness of the films was determined by the cross sectional SEM analysis and its thickness was varied from 920 to 817 nm. The columnar growth of ITO films was also discussed here. The electrical and optical measurements of Ar+O2+H2 ambient combinations shows a decreased sheet resistance (5.06 ohm/□ and increased optical transmittance (69% than other samples. The refractive index and packing density of the films were projected using optical transmission spectrum. From the observed results the Ar+O2+H2 ambient is a good choice to enhance the total optoelectronic properties of the ITO

  12. Effect of ambient combinations of argon, oxygen, and hydrogen on the properties of DC magnetron sputtered indium tin oxide films

    Energy Technology Data Exchange (ETDEWEB)

    Marikkannan, M. [Department of Materials Science, School of Chemistry, Madurai Kamaraj University, Tamil Nadu, Madurai-625021 (India); Subramanian, M.; Tanemura, M. [Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Mayandi, J., E-mail: pearce@mtu.edu, E-mail: jeyanthinath@yahoo.co.in [Department of Materials Science, School of Chemistry, Madurai Kamaraj University, Tamil Nadu, Madurai-625021 (India); Department of Materials Science and Engineering, Michigan Technological University (United States); Vishnukanthan, V. [Department of Physics, Centre for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1126 Blindern, N-0318 Oslo (Norway); Pearce, J. M., E-mail: pearce@mtu.edu, E-mail: jeyanthinath@yahoo.co.in [Department of Materials Science and Engineering, Michigan Technological University (United States); Department of Electrical and Computer Engineering, Michigan Technological University (United States)

    2015-01-15

    Sputtering has been well-developed industrially with singular ambient gases including neutral argon (Ar), oxygen (O{sub 2}), hydrogen (H{sub 2}) and nitrogen (N{sub 2}) to enhance the electrical and optical performances of indium tin oxide (ITO) films. Recent preliminary investigation into the use of combined ambient gases such as an Ar+O{sub 2}+H{sub 2} ambient mixture, which was suitable for producing high-quality (low sheet resistance and high optical transmittance) of ITO films. To build on this promising preliminary work and develop deeper insight into the effect of ambient atmospheres on ITO film growth, this study provides a more detailed investigation of the effects of ambient combinations of Ar, O{sub 2}, H{sub 2} on sputtered ITO films. Thin films of ITO were deposited on glass substrates by DC magnetron sputtering using three different ambient combinations: Ar, Ar+O{sub 2} and Ar+O{sub 2}+H{sub 2}. The structural, electrical and optical properties of the three ambient sputtered ITO films were systematically characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), Raman spectroscopy, four probe electrical conductivity and optical spectroscopy. The XRD and Raman studies confirmed the cubic indium oxide structure, which is polycrystalline at room temperature for all the samples. AFM shows the minimum surface roughness of 2.7 nm for Ar+O{sub 2}+H{sub 2} sputtered thin film material. The thickness of the films was determined by the cross sectional SEM analysis and its thickness was varied from 920 to 817 nm. The columnar growth of ITO films was also discussed here. The electrical and optical measurements of Ar+O{sub 2}+H{sub 2} ambient combinations shows a decreased sheet resistance (5.06 ohm/□) and increased optical transmittance (69%) than other samples. The refractive index and packing density of the films were projected using optical transmission spectrum. From the observed results the Ar+O{sub 2}+H

  13. Improvement of oxygen supply by an artificial carrier in combination with normobaric oxygenation decreases the volume of tissue hypoxia and tissue damage from transient focal cerebral ischemia

    NARCIS (Netherlands)

    Seiffge, David J.; Lapina, Natalia E.; Tsagogiorgas, Charalambos; Theisinger, Bastian; Henning, Robert H.; Schilling, Lothar

    2012-01-01

    Tissue hypoxia may play an important role in the development of ischemic brain damage. In the present study we investigated in a rat model of transient focal brain ischemia the neuroprotective effects of increasing the blood oxygen transport capacity by applying a semifluorinated alkane (SFA)-contai

  14. Relative humidity across the Paleocene-Eocene Thermal Maximum via combined hydrogen-oxygen isotope paleohygrometry (Invited)

    Science.gov (United States)

    McInerney, F. A.; Bloch, J. I.; Secord, R.; Wing, S. L.; Kraus, M. J.; Boyer, D. M.

    2009-12-01

    The Paleocene-Eocene Thermal Maximum (PETM) presents an opportunity to characterize continental hydrologic changes during rapid and extreme global warming. The Bighorn Basin, Wyoming, USA, has long been recognized for the PETM sequences preserved there and sits in an ideal location for recording hydrologic changes in the interior of North America. The southeast Bighorn Basin is of particular interest because it contains not only alluvial paleosols and vertebrate fossils, but also macrofloral remains from the PETM. The carbon isotope excursion associated with this event is preserved in this part of the Basin in leaf wax lipids, tooth enamel, and bulk organic matter. To characterize the hydrologic changes that occurred during the PETM we are applying a suite of isotopic, paleobotanical and paleopedological approaches to sections in the southeast Bighorn Basin. Reported here are results from the combined hydrogen and oxygen isotope analysis aimed at reconstructing relative humidity. Oxygen isotope ratios (δ18O) of biogenic apatite from mammalian tooth enamel and fish scales vary with environment, physiology and diet. Because mammals are homeothermic, they primarily track surface water values with predictable physiological offsets. Hydrogen isotope ratios (δD) of leaf-wax lipids (long-chain n-alkanes) reflect both meteoric water δD values and additional D-enrichment caused by evapotranspiration. The enrichment factor between water δD and n-alkane δD can therefore be used as a proxy for relative humidity (RH). In this study, δ18O of surface water is estimated using the δ18O of Coryphodon tooth enamel. We use these δ18O values to estimate surface water δD values using the Global Meteoric Water Line (δD = 8δ18O + 10). We then calculate relative humidity from n-alkane δD values using a Craig-Gordon type isotopic model for D-enrichment caused by transpiration from leaves. Results of the combined hydrogen-oxygen isotope paleohygrometer indicate a general rise in

  15. Simultaneous blood flow and blood oxygenation measurements using a combination of diffuse speckle contrast analysis and near-infrared spectroscopy

    Science.gov (United States)

    Seong, Myeongsu; Phillips, Zephaniah; Mai, Phuong Minh; Yeo, Chaebeom; Song, Cheol; Lee, Kijoon; Kim, Jae Gwan

    2016-02-01

    A combined diffuse speckle contrast analysis (DSCA)-near-infrared spectroscopy (NIRS) system is proposed to simultaneously measure qualitative blood flow and blood oxygenation changes in human tissue. The system employs an optical switch to alternate two laser sources at two different wavelengths and a CCD camera to capture the speckle image. Therefore, an optical density can be measured from two wavelengths for NIRS measurements and a speckle contrast can be calculated for DSCA measurements. In order to validate the system, a flow phantom test and an arm occlusion protocol for arterial and venous occlusion were performed. Shorter exposure times (<1 ms) show a higher drop (between 50% and 66%) and recovery of 1/KS2 values after occlusion (approximately 150%), but longer exposure time (3 ms) shows more consistent hemodynamic changes. For four subjects, the 1/KS2 values dropped to an average of 82.1±4.0% during the occlusion period and the average recovery of 1/KS2 values after occlusion was 109.1±0.8%. There was also an approximately equivalent amplitude change in oxyhemoglobin (OHb) and deoxyhemoglobin (RHb) during arterial occlusion (max RHb=0.0085±0.0024 mM/DPF, min OHb=-0.0057±0.0044 mM/DPF). The sensitivity of the system makes it a suitable modality to observe qualitative hemodynamic trends during induced physiological changes.

  16. Protection from neuronal damage induced by combined oxygen and glucose deprivation in organotypic hippocampal cultures by glutamate receptor antagonists.

    Science.gov (United States)

    Strasser, U; Fischer, G

    1995-07-31

    Organotypic hippocampal cultures were exposed to defined periods (30 and 60 min) of combined oxygen and glucose deprivation, mimicking transient ischemic conditions. The involvement of different glutamate receptors in individual hippocampal subfields (CA1, CA3 and dentate gyrus) was studied using antagonists of NMDA (dizocilpine) and AMPA/kainate receptors (CNQX and GYKI 52466). Staining with the fluorescent dye propidium iodide (PI) allowed detection of damaged cells. For quantitative determination of neuronal damage, fluorescence intensity was measured after a 22 h recovery period and was related to maximal fluorescence intensity measured after fixation and PI restaining of the cultures at the end of the experiment. Dizocilpine (10 microM), CNQX (100 microM) and GYKI 52466 (100 microM) provided complete protection in CA1, CA3 and dentate gyrus following the moderate ischemic insult, when the antagonists were present permanently. This indicates that none of the ionotropic glutamate receptor subtypes dominated toxicity in the most sensitive subpopulation of neurons. When applied only during the recovery period protection with dizocilpine (10 microM) or CNQX (100 microM) was drastically reduced by about 60% in the most sensitive area (CA1), but only slightly by 15% in CA3. Therefore the onset of irreversible damage seems to occur earlier in CA1 than in CA3. Blockade of AMPA/kainate receptors by GYKI 52466 (100 microM) offered no neuroprotection if the compound was applied only during the recovery period.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Combinative energy,oxygen deficiency and superconductivity in LnBa2Cu3O7-x (Ln=Nd,Er,Sm)

    Institute of Scientific and Technical Information of China (English)

    王淑霞; 刘文利; 韩圣浩; 张酣

    2003-01-01

    The correlation among the combinative energy, superconductivity, oxygen content, the position of holes in different planes, and the position of holes in the Cu(2)-O plane in LnBa2Cu3O7-x (Ln= Nd, Er, and Sm) has been investigated on the basis of a block model. The results indicate that the combinative energy decreases with increasing Tc in all of these compounds. And also, the combinative energies are obviously different with holes at different positions in the Cu(2)-O plane when the oxygen deficiency is low. However, this difference becomes less with increasing the oxygen deficiency.The effect of the holes in different positions on the combinative energy supplies some clue to the understanding of an unresolved problem, i.e. whether the distribution of carriers in the CuO2 plane is uniform or inhomogeneous. The results not only show that the structural characters, the combinative energy between two structural blocks and the superconductivity are closely interrelated in this class of compounds, but also reveal some differences among these systems. The relationship between the combinative energy and the Tc value in NdBa2Cu3O7-x shows some features different from the systems containing Er or Sm.

  18. Imbalance between oxygen photoreduction and antioxidant capacities in Symbiodinium cells exposed to combined heat and high light stress

    Science.gov (United States)

    Roberty, S.; Fransolet, D.; Cardol, P.; Plumier, J.-C.; Franck, F.

    2015-12-01

    During the last decades, coral reefs have been affected by several large-scale bleaching events, and such phenomena are expected to increase in frequency and severity in the future, thus compromising their survival. High sea surface temperature accompanied by high levels of solar irradiance has been found to be responsible for the induction of oxidative stress ultimately ending with the disruption of the symbiosis between cnidarians and Symbiodinium. For two decades, many studies have pointed to the water-water cycle (WWC) as being one of the primary mediators of this phenomenon, but the impacts of environmental stress on the O2 reduction by PSI and the associated reactive oxygen species (ROS)-detoxifying enzymes remain to be determined. In this study, we analyzed the impacts of acute thermal and light stress on the WWC in the model Symbiodinium strain A1. We observed that the high light treatment at 26 °C resulted in the up-regulation of superoxide dismutase, ascorbate peroxidase, and glutathione reductase activities and an increased production of ROS with no significant change in O2-dependent electron transport. Under high light and at 33 °C, O2-dependent electron transport was significantly increased relative to total electron transport. This increase was concomitant with a twofold increase in ROS generation compared with the treatment at 26 °C, while enzymes involved in the WWC were largely inactivated. These data show for the first time that combined heat and light stress inactivate antioxidant capacities of the WWC and suggests that its photoprotective functions are overwhelmed under these conditions. This study also indicates that cnidarians may be more prone to bleach if they harbor Symbiodinium cells having a highly active Mehler-type electron transport, unless they are able to quickly up-regulate their antioxidant capacities.

  19. Comparison of oral midazolam with a combination of oral midazolam and nitrous oxide-oxygen inhalation in the effectiveness of dental sedation for young children

    Directory of Open Access Journals (Sweden)

    Al-Zahrani A

    2009-03-01

    Full Text Available Aim: To compare the effectiveness of 0.6 mg/kg oral midazolam sedation alone and a combination of 0.6 mg/kg oral midazolam plus nitrous oxide-oxygen inhalation sedation, in controlling the behavior of uncooperative children during dental treatment. Study Design: The study had a crossover design where the same patient received two different sedation regimens, that is, oral midazolam 0.6 mg/kg and oral midazolam 0.6 mg/kg with nitrous oxide-oxygen inhalation during two dental treatment visits. Materials and Methods: Thirty children (17 males and 13 females were randomly selected for the study, with a mean age of 55.07 (± 9.29 months, ranging from 48 - 72 months. A scoring system suggested by Houpt et al. (1985 was utilized for assessment of the children′s behavior. Results : There was no significant (p > 0.05 difference in the overall behavior assessment between the two sedation regimens, that is, oral midazolam alone and oral midazolam plus nitrous oxide-oxygen. However, the combination of midazolam and nitrous oxide-oxygen showed significantly (p < 0.05 superior results as compared to midazolam alone, in terms of controlling movement and crying during local anesthesia administration and restorative procedures. Conclusion: Compared to oral midazolam alone, a combination of oral midazolam and nitrous oxide inhalation sedation appears to provide more comfort to pediatric dental patients and operators during critical stages of dental treatment.

  20. [EFFICIENCY OF COMBINATION OF ROFLUMILAST AND QUERCETIN FOR CORRECTION OXYGEN- INDEPENDENT MECHANISMS AND PHAGOCYTIC ACTIVITY OF MACROPHAGE CELLS OF PATIENTS WITH ACUTE EXACERBATION OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE WHEN COMBINED WITH CORONARY HEART DISEASE].

    Science.gov (United States)

    Gerych, P; Yatsyshyn, R

    2015-01-01

    Studied oxygen independent reaction and phagocytic activity of macrophage cells of patients with chronic obstructive pulmonary disease (COPD) II-III stage when combined with coronary heart disease (CHD). The increasing oxygen independent reactions monocytes and neutrophils and a decrease of the parameters that characterize the functional state of phagocytic cells, indicating a decrease in the functional capacity of macrophage phagocytic system (MPS) in patients with acute exacerbation of COPD, which runs as its own or in combination with stable coronary heart disease angina I-II. FC. Severity immunodeficiency state in terms of cellular component of nonspecific immunity in patients with acute exacerbation of COPD II-III stage in conjunction with the accompanying CHD increases with the progression of heart failure. Inclusion of basic therapy of COPD exacerbation and standard treatment of coronary artery disease and drug combinations Roflumilastand quercetin causes normalization of phagocytic indices MFS, indicating improved immune status and improves myocardial perfusion in terms of daily ECG monitoring.

  1. XPS of oxygen atoms on Ag(111) and Ag(110) surfaces: accurate study with SAC/SAC-CI combined with dipped adcluster model.

    Science.gov (United States)

    Ishikawa, Atsushi; Nakatsuji, Hiroshi

    2013-08-01

    O1s core-electron binding energies (CEBE) of the atomic oxygens on different Ag surfaces were investigated by the symmetry adapted cluster-configuration interaction (SAC-CI) method combined with the dipped adcluster model, in which the electron exchange between bulk metal and adsorbate is taken into account properly. Electrophilic and nucleophilic oxygens (O(elec) and O(nuc)) that might be important for olefin epoxidation in a low-oxygen coverage condition were focused here. We consider the O1s CEBE as a key property to distinguish the surface oxygen states, and series of calculation was carried out by the Hartree-Fock, Density functional theory, and SAC/SAC-CI methods. The experimental information and our SAC/SAC-CI results indicate that O(elec) is the atomic oxygen adsorbed on the fcc site of Ag(111) and that O(nuc) is the one on the reconstructed added-row site of Ag(110) and that one- and two-electron transfers occur, respectively, to the O(elec) and O(nuc) adclusters from the silver surface.

  2. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy

    OpenAIRE

    2015-01-01

    The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT) and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mic...

  3. Episodes of apnea and bradycardia in the preterm newborn: impact on cerebral oxygenation measured by near-infrared spectrophotometry

    Science.gov (United States)

    Van Huffel, Sabine; Craemers, Johan; Lenaerts, Bart; Daniels, Hans; Naulaers, Gunnar; Casaer, Paul

    1998-12-01

    The objective of this study is to evaluate the effect of episodes of apneas and/or mild bradycardia (heart rate decreases of 10 to 20% or more) on cerebral oxyhemoglobin (HbO2) and reduced hemoglobin (Hb) concentration as measured by Near Infrared Spectrophotometry (NIRS). Measurements were carried out on 7 preterm infants who experienced apneic and bradycardiac events. It is shown how to characterize these events using time-frequency analysis. In addition to NIRS (performed with a NIRO-500 from Hamamatsu, Japan), the heart rate, ECG, peripheral arterial oxygen saturation (measured at the foot) and respiration (abdominal and thoracic pressure, and nasal airflow) were continuously recorded. The impact of apneic events and periodic breathing on these measurements reveals the clinical relevance of NIRS. In particular, we investigate whether these changes in heart rate and respiration also influence HbO2 and reduced Hb concentration in neonatal brain. These changes are characterized, as well as their relationships with the other simultaneously recorded signals such as peripheral arterial oxygen saturation.

  4. Combination of mild hypothermia with neuroprotectants has greater neuroprotective effects during oxygen-glucose deprivation and reoxygenation-mediated neuronal injury.

    Science.gov (United States)

    Gao, Xiao-Ya; Huang, Jian-Ou; Hu, Ya-Fang; Gu, Yong; Zhu, Shu-Zhen; Huang, Kai-Bin; Chen, Jin-Yu; Pan, Su-Yue

    2014-11-18

    Co-treatment of neuroprotective reagents may improve the therapeutic efficacy of hypothermia in protecting neurons during ischemic stroke. This study aimed to find promising drugs that enhance the neuroprotective effect of mild hypothermia (MH). 26 candidate drugs were selected based on different targets. Primary cultured cortical neurons were exposed to oxygen-glucose deprivation and reoxygenation (OGD/R) to induce neuronal damage, followed by either single treatment (a drug or MH) or a combination of a drug and MH. Results showed that, compared with single treatment, combination of MH with brain derived neurotrophic factor, glibenclamide, dizocilpine, human urinary kallidinogenase or neuroglobin displayed higher proportion of neuronal cell viability. The latter three drugs also caused less apoptosis rate in combined treatment. Furthermore, co-treatment of those three drugs and MH decreased the level of reactive oxygen species (ROS) and intracellular calcium accumulation, as well as stabilized mitochondrial membrane potential (MMP), indicating the combined neuroprotective effects are probably via inhibiting mitochondrial apoptosis pathway. Taken together, the study suggests that combined treatment with hypothermia and certain neuroprotective reagents provide a better protection against OGD/R-induced neuronal injury.

  5. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy.

    Directory of Open Access Journals (Sweden)

    A M Poff

    Full Text Available The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mice receiving the combination therapy demonstrated a marked reduction in tumor growth rate and metastatic spread, and lived twice as long as control animals. To further understand the effects of these metabolic therapies, we characterized the effects of high glucose (control, low glucose (LG, ketone supplementation (βHB, hyperbaric oxygen (HBOT, or combination therapy (LG+βHB+HBOT on VM-M3 cells. Individually and combined, these metabolic therapies significantly decreased VM-M3 cell proliferation and viability. HBOT, alone or in combination with LG and βHB, increased ROS production in VM-M3 cells. This study strongly supports further investigation into this metabolic therapy as a potential non-toxic treatment for late-stage metastatic cancers.

  6. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy.

    Science.gov (United States)

    Poff, A M; Ward, N; Seyfried, T N; Arnold, P; D'Agostino, D P

    2015-01-01

    The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT) and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mice receiving the combination therapy demonstrated a marked reduction in tumor growth rate and metastatic spread, and lived twice as long as control animals. To further understand the effects of these metabolic therapies, we characterized the effects of high glucose (control), low glucose (LG), ketone supplementation (βHB), hyperbaric oxygen (HBOT), or combination therapy (LG+βHB+HBOT) on VM-M3 cells. Individually and combined, these metabolic therapies significantly decreased VM-M3 cell proliferation and viability. HBOT, alone or in combination with LG and βHB, increased ROS production in VM-M3 cells. This study strongly supports further investigation into this metabolic therapy as a potential non-toxic treatment for late-stage metastatic cancers.

  7. Combined effects of reduced malaxation oxygen levels and storage time on extra-virgin olive oil volatiles investigated by a novel chemometric approach.

    Science.gov (United States)

    Raffo, Antonio; Bucci, Remo; D'Aloise, Antonio; Pastore, Gianni

    2015-09-01

    Combined effects of oxygen level reduction in the malaxation headspace and storage time up to 6 months on the volatile composition of a monovarietal extra-virgin olive oil (EVOO), obtained from cv. Carboncella olives, were investigated by applying a full factorial design approach (4 oxygen levels × 4 storage times) on EVOOs extracted on an industrial scale in two mills, equipped with "two-phase" and "three-phase" centrifugation systems, respectively. The outcoming data were analysed by the chemometric technique called ANOVA-simultaneous component analysis (ASCA). Both reduction of oxygen malaxation levels and storage time significantly affected the volatile profile of the extracted EVOOs. Reduction of oxygen malaxation levels hindered the formation of lipoxygenase derived volatiles (hexanal, 1-hexanol, (Z)-2-hexenal, (E)-2-hexen-1-ol, (Z)-2-penten-1-ol, 2,4-hexadienals), whereas prolonged storage times were associated with increased levels of autoxidation products (octane, hexanal, C10 hydrocarbons) and other compounds that could originate from exogenous microbial activity (1-octen-3-ol, 6-methyl-5-hepten-2-one, benzaldehyde, methyl salicylate).

  8. A novel method of combining blood oxygenation and blood flow sensitive magnetic resonance imaging techniques to measure the cerebral blood flow and oxygen metabolism responses to an unknown neural stimulus.

    Directory of Open Access Journals (Sweden)

    Aaron B Simon

    Full Text Available Simultaneous implementation of magnetic resonance imaging methods for Arterial Spin Labeling (ASL and Blood Oxygenation Level Dependent (BOLD imaging makes it possible to quantitatively measure the changes in cerebral blood flow (CBF and cerebral oxygen metabolism (CMRO(2 that occur in response to neural stimuli. To date, however, the range of neural stimuli amenable to quantitative analysis is limited to those that may be presented in a simple block or event related design such that measurements may be repeated and averaged to improve precision. Here we examined the feasibility of using the relationship between cerebral blood flow and the BOLD signal to improve dynamic estimates of blood flow fluctuations as well as to estimate metabolic-hemodynamic coupling under conditions where a stimulus pattern is unknown. We found that by combining the information contained in simultaneously acquired BOLD and ASL signals through a method we term BOLD Constrained Perfusion (BCP estimation, we could significantly improve the precision of our estimates of the hemodynamic response to a visual stimulus and, under the conditions of a calibrated BOLD experiment, accurately determine the ratio of the oxygen metabolic response to the hemodynamic response. Importantly we were able to accomplish this without utilizing a priori knowledge of the temporal nature of the neural stimulus, suggesting that BOLD Constrained Perfusion estimation may make it feasible to quantitatively study the cerebral metabolic and hemodynamic responses to more natural stimuli that cannot be easily repeated or averaged.

  9. A novel method of combining blood oxygenation and blood flow sensitive magnetic resonance imaging techniques to measure the cerebral blood flow and oxygen metabolism responses to an unknown neural stimulus.

    Science.gov (United States)

    Simon, Aaron B; Griffeth, Valerie E M; Wong, Eric C; Buxton, Richard B

    2013-01-01

    Simultaneous implementation of magnetic resonance imaging methods for Arterial Spin Labeling (ASL) and Blood Oxygenation Level Dependent (BOLD) imaging makes it possible to quantitatively measure the changes in cerebral blood flow (CBF) and cerebral oxygen metabolism (CMRO(2)) that occur in response to neural stimuli. To date, however, the range of neural stimuli amenable to quantitative analysis is limited to those that may be presented in a simple block or event related design such that measurements may be repeated and averaged to improve precision. Here we examined the feasibility of using the relationship between cerebral blood flow and the BOLD signal to improve dynamic estimates of blood flow fluctuations as well as to estimate metabolic-hemodynamic coupling under conditions where a stimulus pattern is unknown. We found that by combining the information contained in simultaneously acquired BOLD and ASL signals through a method we term BOLD Constrained Perfusion (BCP) estimation, we could significantly improve the precision of our estimates of the hemodynamic response to a visual stimulus and, under the conditions of a calibrated BOLD experiment, accurately determine the ratio of the oxygen metabolic response to the hemodynamic response. Importantly we were able to accomplish this without utilizing a priori knowledge of the temporal nature of the neural stimulus, suggesting that BOLD Constrained Perfusion estimation may make it feasible to quantitatively study the cerebral metabolic and hemodynamic responses to more natural stimuli that cannot be easily repeated or averaged.

  10. Response of CAIX and CAXII to in vitro re-oxygenation and clinical significance of the combined expression in NSCLC patients.

    Science.gov (United States)

    Ilie, Marius; Hofman, Véronique; Zangari, Joséphine; Chiche, Johanna; Mouroux, Jérôme; Mazure, Nathalie M; Pouysségur, Jacques; Brest, Patrick; Hofman, Paul

    2013-10-01

    The disorganized neo-vasculature in tumours causes fluctuations in the concentration of oxygen, which contributes to tumour development and metastatic potential. Although hypoxic regulation of the expression of the carbonic anhydrases CAIX and CAXII is well established, the effect of re-oxygenation on these proteins remains to be elucidated. A549 and H1975 human lung cancer cell lines were exposed to hypoxia for 24 h and then re-oxygenated. CAIX or CAXII expression and cell cycle progression at different time-points were monitored. A549-shCA9 cells were analyzed for cell cycle progression in the same conditions. We demonstrate for the first time an association between the stability of CAIX and restoration of the S/G2 phase of hypoxia-arrested cells subjected to re-oxygenation. In exchange, we have found that the loss of CA9 did not cause a decreased progression into S/G2 phase during re-oxygenation, but rather affected the hypoxic growth arrest. We previously demonstrated that CAIX expression is a poor prognostic factor and that CAXII expression is a good prognostic factor in non-small cell lung cancer (NSCLC) patients. We further detail the relevance of the combined expression of these proteins for predicting outcome in a large population of NSCLC patients after long-term follow-up. The high CAIX/low CAXII expression sub-group was associated with a high cumulative incidence of relapse and with poor overall survival of NSCLC patients (P cancer phenotype. These findings suggest that CAIX and CAXII play dual roles in tumour progression and emphasize their significant prognostic and potential therapeutic value.

  11. Pre-dive Whole-Body Vibration Better Reduces Decompression-Induced Vascular Gas Emboli than Oxygenation or a Combination of Both

    Science.gov (United States)

    Balestra, Costantino; Theunissen, Sigrid; Papadopoulou, Virginie; Le Mener, Cedric; Germonpré, Peter; Guerrero, François; Lafère, Pierre

    2016-01-01

    Purpose: Since non-provocative dive profiles are no guarantor of protection against decompression sickness, novel means including pre-dive “preconditioning” interventions, are proposed for its prevention. This study investigated and compared the effect of pre-dive oxygenation, pre-dive whole body vibration or a combination of both on post-dive bubble formation. Methods: Six healthy volunteers performed 6 no-decompression dives each, to a depth of 33 mfw for 20 min (3 control dives without preconditioning and 1 of each preconditioning protocol) with a minimum interval of 1 week between each dive. Post-dive bubbles were counted in the precordium by two-dimensional echocardiography, 30 and 90 min after the dive, with and without knee flexing. Each diver served as his own control. Results: Vascular gas emboli (VGE) were systematically observed before and after knee flexing at each post-dive measurement. Compared to the control dives, we observed a decrease in VGE count of 23.8 ± 7.4% after oxygen breathing (p < 0.05), 84.1 ± 5.6% after vibration (p < 0.001), and 55.1 ± 9.6% after vibration combined with oxygen (p < 0.001). The difference between all preconditioning methods was statistically significant. Conclusions: The precise mechanism that induces the decrease in post-dive VGE and thus makes the diver more resistant to decompression stress is still not known. However, it seems that a pre-dive mechanical reduction of existing gas nuclei might best explain the beneficial effects of this strategy. The apparent non-synergic effect of oxygen and vibration has probably to be understood because of different mechanisms involved. PMID:27965591

  12. Effect of hyperbaric oxygen combined withα-lipoic acid on neurological function and serum indexes of patients with diabetic peripheral neuropathy

    Institute of Scientific and Technical Information of China (English)

    Yu Li; Ling Qi; Jun Li

    2016-01-01

    Objective:To analyze the effect of hyperbaric oxygen combined withα-lipoic acid on neurological function and serum indexes of patients with diabetic peripheral neuropathy. Methods:A total of 118 diabetic peripheral neuropathy patients who received treatment in our hospital were selected as research subjects, and according to the different clinical treatment they received, all included patients were divided into observation group 59 cases and control group 59 cases. Control group received conventional clinical treatment, and observation group received additional hyperbaric oxygen combined withα-lipoic acid treatment. Differences in nerve conduction velocity, gastrocnemius nerve threshold, illness-related factors, oxidative stress indicator values, and so on were compared between two groups after treatment.Results:MCV and SCV values of median nerve, ulnar nerve and tibial nerve of observation group after treatment were higher than those of control group (P<0.05); gastrocnemius nerve threshold of observation group after treatment were significantly lower than those of control group (P<0.05); serum CP and BDNF values of observation group after treatment were higher than those of control group while Cys-C, SDF-1α, HMGB1 and MBP values were lower than those of control group (P<0.05); serum MDA and NO values of observation group after treatment were lower than those of control group while SOD, CAT and GSH-Px values were higher than those of control group (P<0.05).Conclusions:Hyperbaric oxygen combined withα-lipoic acid is a good method to optimize the neurological function and improve overall illness of patients with diabetic peripheral neuropathy, and is expected to become a new way of inhibiting disease progression and improving disease outcome.

  13. Combination multinitrogen with good oxygen balance: molecule and synthesis design of polynitro-substituted tetrazolotriazine-based energetic compounds.

    Science.gov (United States)

    He, Piao; Zhang, Jian-Guo; Wang, Kun; Yin, Xin; Zhang, Tong-Lai

    2015-06-01

    We investigated 5,8-dinitro-5,6,7,8-tetrahydrotetrazolo[1,5-b][1,2,4]triazine (short for DNTzTr (1)) using various ab initio quantum chemistry methods. We proposed an additional three novel polynitro-substituted tetrazolotriazine-based compounds with exceptional performance, including 5,8-dinitro-5,6-dioxotetrazolo[1,5-b][1,2,4]triazine, DNOTzTr (2), 4,5,9,10-tetranitro[1,2,4,5]tetrazolo[3,4-b][1,2,4,5]tetrazolo[3',4':5,6]triazino[2,3-e]triazine, TNTzTr (3), and 4,5,6,10,11,12-hexanitro-bis[1,2,4,5]tetrazolo[3',4':5,6]triazino[2,3-b:2',3'-e]triazine, HNBTzTr (4). The optimized structure, electronic density, natural bond orbital (NBO) charges and HOMO-LUMO orbitals, electrostatic potential on surface of molecule, IR- and NMR-predicted spectra, as well as thermochemical parameters were calculated with the B3LYP/6-311+G(2d) level of theory. Critical parameters such as density, enthalpy of formation (EOF), and detonation performance have also been predicted. Characters with positive EOF (1386.00 and 1625.31 kJ/mol), high density (over 2.00 g/cm(3)), outstanding detonation properties (D = 9.82 km/s, P = 45.45 GPa; D = 9.94 km/s, P = 47.30 GPa), the perfect oxygen balance set to zero, and acceptable impact sensitivity led novel compounds 3 and 4 to be very promising energetic materials. This work provides the theoretical molecule design and a reasonable synthesis path for further experimental synthesis and testing.

  14. Feasibility of actinide separation from UREX-like raffinates using a combination of sulfur- and oxygen-donor extractants

    Energy Technology Data Exchange (ETDEWEB)

    Peter R. Zalupski; Dean R. Peterman; Catherine L. Riddle

    2013-09-01

    A synergistic combination of bis(o-trifluoromethylphenyl)dithiosphosphinic acid and trioctylphosphine oxide has been recently shown to selectively remove uranium, neptunium, plutonium and americium from aqueous environment containing up to 0.5 M nitric acid and 5.5 g/L fission products. Here the feasibility of performing this complete actinide recovery from aqueous mixtures is forecasted for a new organic formulation containing sulfur donor extractant of modified structure based on Am(III) and Eu(III) extraction data. A mixture of bis(bis-m,m-trifluoromethyl)phenyl)-dithiosphosphinic acid and TOPO in toluene enhances the extraction performance, accomplishing Am/Eu differentiation in aqueous mixtures up to 1 M nitric acid. The new organic recipe is also less susceptible to oxidative damage resulting from radiolysis.

  15. Synergistic anticandidal activity of pure polyphenol curcumin I in combination with azoles and polyenes generates reactive oxygen species leading to apoptosis.

    Science.gov (United States)

    Sharma, Monika; Manoharlal, Raman; Negi, Arvind Singh; Prasad, Rajendra

    2010-08-01

    We have shown previously that pure polyphenol curcumin I (CUR-I) shows antifungal activity against Candida species. By employing the chequerboard method, filter disc and time-kill assays, in the present study we demonstrate that CUR-I at non-antifungal concentration interacts synergistically with azoles and polyenes. For this, pure polyphenol CUR-I was tested for synergy with five azole and two polyene drugs - fluconazole (FLC), miconazole, ketoconazole (KTC), itraconazole (ITR), voriconazole (VRC), nystatin (NYS) and amphotericin B (AMB) - against 21 clinical isolates of Candida albicans with reduced antifungal sensitivity, as well as a drug-sensitive laboratory strain. Notably, there was a 10-35-fold drop in the MIC(80) values of the drugs when CUR-I was used in combination with azoles and polyenes, with fractional inhibitory concentration index (FICI) values ranging between 0.09 and 0.5. Interestingly, the synergistic effect of CUR-I with FLC and AMB was associated with the accumulation of reactive oxygen species, which could be reversed by the addition of an antioxidant such as ascorbic acid. Furthermore, the combination of CUR-I and FLC/AMB triggered apoptosis that could also be reversed by ascorbic acid. We provide the first evidence that pure CUR-I in combination with azoles and polyenes represents a novel therapeutic strategy to improve the activity of common antifungals.

  16. Hydrogen production from a combination of the water-gas shift and redox cycle process of methane partial oxidation via lattice oxygen over LaFeO3 perovskite catalyst.

    Science.gov (United States)

    Dai, Xiao Ping; Wu, Qiong; Li, Ran Jia; Yu, Chang Chun; Hao, Zheng Ping

    2006-12-28

    A redox cycle process, in which CH4 and air are periodically brought into contact with a solid oxide packed in a fixed-bed reactor, combined with the water-gas shift (WGS) reaction, is proposed for hydrogen production. The sole oxidant for partial oxidation of methane (POM) is found to be lattice oxygen instead of gaseous oxygen. A perovskite-type LaFeO3 oxide was prepared by a sol-gel method and employed as an oxygen storage material in this process. The results indicate that, under appropriate reaction conditions, methane can be oxidized to CO and H2 by the lattice oxygen of LaFeO3 perovskite oxide with a selectivity higher than 95% and the consumed lattice oxygen can be replenished in a reoxidation procedure by a redox operation. It is suggested that the POM to H2/CO by using the lattice oxygen of the oxygen storage materials instead of gaseous oxygen should be possibly applicable. The LaFeO3 perovskite oxide maintained relatively high catalytic activity and structural stability, while the carbonaceous deposits, which come from the dissociation of CH4 in the pulse reaction, occurred due to the low migration rate of lattice oxygen from the bulk toward the surface. A new dissociation-oxidation mechanism for this POM without gaseous oxygen is proposed based on the transient responses of the products checked at different surface states via both pulse reaction and switch reaction over the LaFeO3 catalyst. In the absence of gaseous-phase oxygen, the rate-determining step of methane conversion is the migration rate of lattice oxygen, but the process can be carried out in optimized cycles. The product distribution for POM over LaFeO3 catalyst in the absence of gaseous oxygen was determined by the concentration of surface oxygen, which is relevant with the migration rate of lattice oxygen from the bulk toward the surface. This process of hydrogen production via selective oxidation of methane by lattice oxygen is better in avoiding the deep oxidation (to CO2) and

  17. 低氧富氮结合脱氧剂储粮技术探索%Exploration of Grain Storage Technology Using Deoxidizing Agent Combined with Low Oxygen Nitrogen-rich

    Institute of Scientific and Technical Information of China (English)

    常亚飞; 孙俊; 陈彩根

    2014-01-01

    通过对不同粮堆分别进行低氧富氮、脱氧剂结合低氧富氮、脱氧剂等储藏效果的对比,脱氧剂结合低氧富氮技术相对于单独使用脱氧剂和低氧富氮更加经济有效。%For different grain piles, we use the different storage methods such as using low oxygen nitrogen-rich, deoxidizing agent combined with low oxygen nitrogen-rich and deoxidizer, the results show, deoxidizing agent combined with low oxygen nitrogen-rich storage technology is more effectively and economically than the storage technology using deoxidizers and low oxygen nitrogen-rich.

  18. Oxygen Therapy

    Science.gov (United States)

    Oxygen therapy is a treatment that provides you with extra oxygen. Oxygen is a gas that your body needs to function. Normally, your lungs absorb oxygen from the air you breathe. But some conditions ...

  19. Protection against Oxygen-Glucose Deprivation/Reperfusion Injury in Cortical Neurons by Combining Omega-3 Polyunsaturated Acid with Lyciumbarbarum Polysaccharide.

    Science.gov (United States)

    Shi, Zhe; Wu, Di; Yao, Jian-Ping; Yao, Xiaoli; Huang, Zhijian; Li, Peng; Wan, Jian-Bo; He, Chengwei; Su, Huanxing

    2016-01-13

    Ischemic stroke, characterized by the disturbance of the blood supply to the brain, is a severe worldwide health threat with high mortality and morbidity. However, there is no effective pharmacotherapy for ischemic injury. Currently, combined treatment is highly recommended for this devastating injury. In the present study, we investigated neuroprotective effects of the combination of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) and Lyciumbarbarum polysaccharide (LBP) on cortical neurons using an in vitro ischemic model. Our study demonstrated that treatment with docosahexaenoic acid (DHA), a major component of the ω-3 PUFAs family, significantly inhibited the increase of intracellular Ca(2+) in cultured wild type (WT) cortical neurons subjected to oxygen-glucose deprivation/reperfusion (OGD/R) injury and promoted their survival compared with the vehicle-treated control. The protective effects were further confirmed in cultured neurons with high endogenous ω-3 PUFAs that were isolated from fat-1 mice, in that a higher survival rate was found in fat-1 neurons compared with wild-type neurons after OGD/R injury. Our study also found that treatment with LBP (50 mg/L) activated Trk-B signaling in cortical neurons and significantly attenuated OGD/R-induced cell apoptosis compared with the control. Notably, both combining LBP treatment with ω-3 PUFAs administration to WT neurons and adding LBP to fat-1 neurons showed enhanced effects on protecting cortical neurons against OGD/R injury via concurrently regulating the intracellular calcium overload and neurotrophic pathway. The results of the study suggest that ω-3 PUFAs and LBP are promising candidates for combined pharmacotherapy for ischemic stroke.

  20. Combined application of dexamethasone and hyperbaric oxygen therapy yields better efficacy for patients with delayed encephalopathy after acute carbon monoxide poisoning

    Science.gov (United States)

    Xiang, Wenping; Xue, Hui; Wang, Baojun; Li, Yuechun; Zhang, Jun; Jiang, Changchun; Liang, Furu; Pang, Jiangxia; Yu, Lehua

    2017-01-01

    Background Delayed encephalopathy after acute carbon monoxide (CO) poisoning (DEACMP) commonly occurs after recovering from acute CO poisoning. This study was performed to assess the efficacy of the combined application of dexamethasone and hyperbaric oxygen (HBO) therapy in patients with DEACMP. Patients and methods A total of 120 patients with DEACMP were recruited and randomly assigned into the experimental group (receiving dexamethasone 5 mg/day or 10 mg/day plus HBO therapy) and control group (HBO therapy as monotherapy). Meanwhile, the conventional treatments were provided for all the patients. We used the Mini-Mental State Examination (MMSE) scale to assess the cognitive function, the National Institutes of Health Stroke Scale (NIHSS) to assess the neurological function and the remission rate (RR) to assess the clinical efficacy. Myelin basic protein (MBP) in the cerebrospinal fluid (CSF) was also measured. Results After 4 weeks of treatment, compared to the control group, the experimental group had a significantly higher remission rate (P=0.032), a significantly higher average MMSE score (P=0.037) and a significantly lower average NIHSS score (P=0.002). Meanwhile, there was a trend toward better improvement with dexamethasone 10 mg/day, and the level of MBP in the CSF of patients was significantly lower in the experimental group than in the control group (P<0.0001). The addition of dexamethasone did not significantly increase the incidence of adverse events. Conclusion These results indicate that the combined application of dexamethasone and HBO therapy could yield better efficacy for patients with DEACMP and should be viewed as a potential new therapy. PMID:28260864

  1. Antiproliferation of Berberine in Combination with Fluconazole from the Perspectives of Reactive Oxygen Species, Ergosterol and Drug Efflux in a Fluconazole-Resistant Candida tropicalis Isolate

    Science.gov (United States)

    Shao, Jing; Shi, GaoXiang; Wang, TianMing; Wu, DaQiang; Wang, ChangZhong

    2016-01-01

    Candida tropicalis has emerged as an important pathogenic fungus in nosocomial infections due to its recalcitrant resistance to conventional antifungal agents, especially to fluconazole (FLC). Berberine (BBR) is a bioactive herbal-originated alkaloids and has been reported to possess antifungal functions against C. albicans. In this paper, we tried to figure out the antifungal mechanisms of BBR and/or FLC in a clinical C. tropicalis isolate 2006. In the microdilution test, the minimum inhibitory concentration (MIC) of BBR was found 16 μg/mL with fractional inhibitory concentration index (FICI) 0.13 in C. tropicalis 2006. The synergism of BBR and FLC was also confirmed microscopically. After the treatments of BBR and/or FLC, the studies revealed that (i) FLC facilitated BBR to increase reactive oxygen species (ROS), (ii) FLC enhanced the intranuclear accumulation of BBR, (iii) BBR decreased the extracellular rhodamine 123 (Rh123) via inhibiting efflux transporters, (iv) FLC assisted BBR to reduce ergosterol content, and (v) BBR in combined with FLC largely downregulated the expressions of Candida drug resistance 1 (CDR1) and CDR2 but impact slightly multidrug resistance 1 (MDR1), and upregulate the expression of ergosterol 11 (ERG11). These results suggested that BBR could become a potent antifungal drug to strengthen FLC efficacy in FLC-resistant C. tropicalis via ROS increase, intracellular BBR accumulation, ergosterol decrease and efflux inhibition. PMID:27721812

  2. Highly reduced current collapse in AlGaN/GaN high-electron-mobility transistors by combined application of oxygen plasma treatment and field plate structures

    Science.gov (United States)

    Asubar, Joel T.; Yoshida, Satoshi; Tokuda, Hirokuni; Kuzuhara, Masaaki

    2016-04-01

    We report on the highly reduced current collapse in AlGaN/GaN high-electron-mobility transistors (HEMTs) by combined application of pre-passivation oxygen (O2) plasma treatment and gate field plate (FP) structures schemes. Four different devices were fabricated in this work: (1) conventional HEMT as reference device, (2) field-plated HEMT, (3) O2 plasma-treated HEMT, (4) both field-plated and O2 plasma-treated HEMT. Analysis of dependence of normalized dynamic R on (NDR) on gate pulse on-time (t on) revealed that gate-FP reduces the emission time constant (τ i ) of trapped electrons while O2-plasma treatment decreases the density of traps. For all measurement conditions, the device with both FP and O2 plasma treatment exhibited the least NDR compared to devices with either FP or O2 plasma treatment only, demonstrating for the first time the compatibility of both O2 plasma treatment and FP schemes in mitigating current collapse.

  3. Development of variable pathlength UV-vis spectroscopy combined with partial-least-squares regression for wastewater chemical oxygen demand (COD) monitoring.

    Science.gov (United States)

    Chen, Baisheng; Wu, Huanan; Li, Sam Fong Yau

    2014-03-01

    To overcome the challenging task to select an appropriate pathlength for wastewater chemical oxygen demand (COD) monitoring with high accuracy by UV-vis spectroscopy in wastewater treatment process, a variable pathlength approach combined with partial-least squares regression (PLSR) was developed in this study. Two new strategies were proposed to extract relevant information of UV-vis spectral data from variable pathlength measurements. The first strategy was by data fusion with two data fusion levels: low-level data fusion (LLDF) and mid-level data fusion (MLDF). Predictive accuracy was found to improve, indicated by the lower root-mean-square errors of prediction (RMSEP) compared with those obtained for single pathlength measurements. Both fusion levels were found to deliver very robust PLSR models with residual predictive deviations (RPD) greater than 3 (i.e. 3.22 and 3.29, respectively). The second strategy involved calculating the slopes of absorbance against pathlength at each wavelength to generate slope-derived spectra. Without the requirement to select the optimal pathlength, the predictive accuracy (RMSEP) was improved by 20-43% as compared to single pathlength spectroscopy. Comparing to nine-factor models from fusion strategy, the PLSR model from slope-derived spectroscopy was found to be more parsimonious with only five factors and more robust with residual predictive deviation (RPD) of 3.72. It also offered excellent correlation of predicted and measured COD values with R(2) of 0.936. In sum, variable pathlength spectroscopy with the two proposed data analysis strategies proved to be successful in enhancing prediction performance of COD in wastewater and showed high potential to be applied in on-line water quality monitoring.

  4. Using oxygen at home

    Science.gov (United States)

    Oxygen - home use; COPD - home oxygen; Chronic obstructive airways disease - home oxygen; Chronic obstructive lung disease - home oxygen; Chronic bronchitis - home oxygen; Emphysema - home oxygen; Chronic respiratory ...

  5. The effect of oxygen vacancies on the structure and electrochemistry of LiTi{sub 2}(PO{sub 4}){sub 3} for lithium-ion batteries: A combined experimental and theoretical study

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Jia-Yan; He, Ping; Xia, Yong-Yao [Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Institute of New Energy, Fudan University, Handan Road 220, Shanghai 200433 (China); Chen, Li-Juan; Zhao, Yu-Jun [Department of Physics, South China University of Technology, Guangzhou 510640 (China)

    2009-12-01

    We report that a partially oxygen deficient LiTi{sub 2}(PO{sub 4}){sub 3} shows a much better rate capability as a cathode material for lithium-ion batteries compared to stoichiometric LiTi{sub 2}(PO{sub 4}){sub 3}. A combination of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemistry, and first-principles calculations was used to determine and rationalize the structural and electrical changes that occur with different heat treatment atmospheres. XRD and XPS experiments confirmed that some Ti{sup 4+} transformed to Ti{sup 3+} in oxygen deficient LiTi{sub 2}(PO{sub 4}){sub 3} heat treated under N{sub 2}; Ti{sup 3+} was detected and the lattice parameter increased compared to that of LiTi{sub 2}(PO{sub 4}){sub 3}. Electrical conductivity measurements indicated an increase in the electronic conductivity of nearly two orders of magnitude for the oxygen deficient LiTi{sub 2}(PO{sub 4}){sub 3} sample compared to LiTi{sub 2}(PO{sub 4}){sub 3}. First-principles calculations suggest that the oxygen vacancies could be formed in LiTi{sub 2}(PO{sub 4}){sub 3} under oxygen-poor conditions, and this may significantly decrease the donor levels of other possible donor defects and thus improve the electronic mobility. (author)

  6. A new method combining soil oxygen concentration measurements with the quantification of gross nitrogen turnover rates and associated formation of N2O and N2 emissions

    Science.gov (United States)

    Gütlein, Adrian; Dannenmann, Michael; Sörgel, Christoph; Meier, Rudi; Meyer, Astrid; Kiese, Ralf

    2014-05-01

    Climate change and the expansion of land use have led to significant changes in terrestrial ecosystems. These include changes in the biogeochemical cycle of nitrogen and therewith implications for biodiversity, water cycle and pedosphere-atmosphere exchange. To understand these impacts detailed research on nitrogen turnover and fluxes are conducted at various (semi-) natural and managed ecosystems in the Mt. Kilimanjaro region. In this context, we execute 15N tracing analyses on soil samples in our stable isotope laboratory including a new experimental setup. The soils were sampled from different forest ecosystems of Mt. Kilimanjaro varying in altitude (1600 - 4500 m) and will be analyzed for gross rates of ammonification and nitrification, gross rates of microbial inorganic N uptake as well as for the gaseous losses of ^15N2 and ^15N2O using ^15NH4+ and ^15NO3- tracing and pool dilution approaches. Since nitrogen turnover of nitrification and denitrification is dependent on soil oxygen concentrations we developed an incubation method which allows to adjust soil samples to different oxygen concentrations. For this purpose, soil is incubated in glass bottles with side tubes to ensure a constant gas flow over the whole incubation time. To adjust the oxygen levels in the laboratory experiment as close as possible to the natural conditions, we started to monitor soil oxygen concentrations with a FirestingO2 Sensor (Pyroscience) connected to a timer and a datalogger (MSR 145 IP 60 E3333) at a Mt. Kilimanjaro rainforest site. The equipment is complemented with soil temperature, moisture and pressure sensors (MSR 145 IP 60). A solar panel connected to an energy source guarantees a working time for over 2 years by a measuring frequency of 20 seconds each 30 minutes. The new laboratory incubation method together with in-situ oxygen concentration measurements in soils will facilitate laboratory incubations with realistic oxygen concentrations and thus will allow for a better

  7. Microeukaryotic community and oxygen response in rice field soil revealed using a combined rRNA-gene and rRNA-based approach.

    Science.gov (United States)

    Murase, Jun; Takenouchi, Yuriko; Iwasaki, Kazufumi; Kimura, Makoto

    2014-01-01

    Irrigated rice field soil is subjected to frequent changes in oxygen status due to the water regime by agricultural management. In this study, the community response of microeukaryotes in rice field soil to the oxygen status was explored in a microcosm experiment under defined conditions. Water-saturated soil was incubated under a two-level factorial design of oxygen and organic enrichment with plant residue. The eukaryotic microbial community composition, which was either present or potentially active in the soils, was analyzed using denaturing gradient gel electrophoresis (DGGE) targeting the 18S rRNA gene or reverse-transcribed 18S rRNA. Oxygen availability was a primary factor shaping the microeukaryotic community in both DNA- and RNA-based analyses, revealing a shift within a week of incubation. Plant residue also affected the microeukaryotic community, which was more notable in the active community showing rRNA expression with time. Sequences of amplicons in DGGE bands indicated that protozoa (ciliates, flagellates, and amoebae) were the most prominent microeukaryotes in water-saturated rice field soil both in DNA- and RNA-based analyses. The use of a modified primer for soil protozoa suggested the functional importance of Heterolobosea amoeba in rice field soil, particularly in anoxic soil with organic enrichment.

  8. Oxygen vacancies on TiO2(110) and their interaction with H2O and O2: A combined high-resolution STM and DFT study

    DEFF Research Database (Denmark)

    Wendt, Stefan; Schaub, Renald; Matthiesen, Jesper;

    2005-01-01

    From an interplay between high-resolution scanning tunneling microscopy (STM) and density functional theory (DFT) we discuss the origin of various point defects on reduced rutile TiO2(110)–(1 × 1) surfaces. By means of adsorption and desorption experiments using water and oxygen as probe molecule...

  9. Effects of Extracorporeal Shock Wave Therapy Combined with Hyperbaric Oxygen on Nonunion of Long Bone Fractures%冲击波联合高压氧治疗长骨骨折不愈合的疗效分析

    Institute of Scientific and Technical Information of China (English)

    王海东; 杨智权; 张平; 张庆民; 徐啸; 李贵忠; 黄广林; 满立波

    2014-01-01

    Objective To explore the effect of extracorporeal shock wave therapy (ESWT) combined with hyperbaric oxygen on non-union after surgery. Methods 83 patients with nonunion were treated with ESWT combined with hyperbaric oxygen (treatment group), and 32 cases served as control group. ESWT application was conducted using a protocol totaling 3000 shocks per treatment. The treatment group received 3~5 times of treatment, at the same time hyperbaric oxygen therapy was performed. The control group received no treatment and was followed up at least 3 months after treatment. Results The overall success rate was 78.31% in the treatment group, while only 12.50%recovered in the control group (P<0.01). The complications of treatment group were less and negligible. Conclusion Treatment of nonunion by extracorporeal shock wave combined with hyperbaric oxygen is safe and effective.%目的:探讨体外冲击波疗法(ESWT)联合高压氧对骨折不愈合的治疗效果。方法将115例骨折不愈合患者分为ESWT联合高压氧治疗组(治疗组,n=83)和对照组(n=32)。治疗组采用ESWT治疗3~5次,每次治疗冲击计量3000次,期间配合高压氧治疗。对照组继续观察,随访3个月以上。结果治疗组总治愈率为78.31%,对照组为12.50%(P<0.01)。治疗组并发症少且轻微。结论 ESWT联合高压氧治疗骨折不愈合安全有效。

  10. 高压氧加药物综合治疗突发性耳聋疗效分析%Therapeutic Effect of Hyperbaric Oxygen Combined with Medical Treatment on Sudden Deafness

    Institute of Scientific and Technical Information of China (English)

    黄红星; 杨立; 黄远; 唐梓轩; 赵之栋

    2011-01-01

    目的 探讨高压氧联合药物治疗突发性耳聋(sudden deafness,SD)的疗效.方法 2008年2月- 2010年7月,对174例SD患者采用高压氧(治疗压力0.2 MPa)及配合扩血管、营养神经等药物进行治疗,并观察其疗效.结果 高压氧联合药物治疗SD总有效率为85.7%,SD的发病就诊时间是影响预后的主要因素,发病就诊时间≤7d时,治疗有效率可达95.6%;≥15 d时,疗效明显降低.结论 高压氧联合药物治疗SD疗效确切,且高压氧治疗越早疗效越好.%Objective To observe the therapeutic effect of hyperbaric oxygen combined with medical treatment on sudden deafness. Methods Between February 2008 and July 2010, 174 patients with sudden deafness were treated by a combined therapy, including hyperbaric oxygen and medicals. The therapeutic effect was analyzed. Results The total effective rate was 85. 7%. The simultaneous phenomenon such as vertigo and vomiting and onset-diagnosis duration were the two major factors affecting the prognosis. When the onset-diagnosis duration was <[7 days, the effective rate reached 95. 6%; when the onset-diagnosis duration was≥15 days, the therapeutic effect decreased significantly. Conclusion Hyperbaric oxygen combined with medical treatment is effective for sudden deafness, and the hyperbaric oxygen treatment should be performed as earlier as possible.

  11. 常温空分氧氮一体化联合分离系统%Design of Combined Air Separation System for Oxygen-Nitrogen at Normal Temperature

    Institute of Scientific and Technical Information of China (English)

    薛敏; 金正涛

    2011-01-01

    总结了目前船用分立制氧、制氮系统和氧、氮提纯系统的不足之处,得出开发常温空分氧氮一体化联合分离系统的必要性.在此基础上,探讨了常温空分氧氮一体化联合分离系统的总体设计,构建了一种基于常温空分的联合制氧、制氮的创新系统方案,即以变压吸附技术与膜分离技术耦合的工艺技术对空气组分进行分离,仅以空气为原料,无需任何辅料,在仅消耗电力资源的情况下同时获取氧气和氮气.最后指出了常温空分氧氮一体化联合分离系统的发展趋势和应用范围.%Current independent marine separators for individual oxygen & nitrogen generation along with purification system has many drawbacks, it necessitates the development of combined air separation system for oxygen-nitrogen. This paper gives a concept of overall design of such combined system at normal temperature condition. A novel scheme of combined solution for generating oxygen and nitrogen is presented. This design incorporates PSA-membrane separation technique, raw material used for separation process is air, consuming electric power and dispensing with any accessories. The paper also presents trends for the development of combined air separation system at normal temperature and indicates a range of applications possible in the future ship design.

  12. Pre-treatment ferritin level and alveolar-arterial oxygen gradient can predict mortality rate due to acute/subacute interstitial pneumonia in dermatomyositis treated by cyclosporine a/glucocorticosteroid combination therapy: a case control study [corrected].

    Directory of Open Access Journals (Sweden)

    Kentaro Isoda

    Full Text Available BACKGROUND: Acute/subacute interstitial pneumonia in dermatomyositis (DM-A/SIP is a disease associated with a poor prognosis that resists treatment with glucocorticosteroids (GC and progresses rapidly in a period of weeks to months to death. We retrospectively studied outcomes, prognostic factors, and their relations with survival rate in patients with DM-A/SIP treated with early cyclosporine A (CSA/GC combination therapy and 2-hour postdose blood concentration monitoring. METHODS: This study comprised 32 DM-A/SIP patients who were simultaneously treated with CSA and prednisolone. Clinical and laboratory findings were compared between those who died due to DM-A/SIP and those surviving 24 weeks after beginning of therapy. Prognostic factors were extracted, and their relations with the survival rate were evaluated. RESULTS: Of the 32 DM-A/SIP patients, 25 survived, 5 died of DM-A/SIP, and 2 died of infections. In those who died due to DM-A/SIP, ferritin level and the alveolar-arterial oxygen gradient were significantly increased compared with the survivors (P<0.001 and P = 0.002, respectively. Multivariate analyses showed that ferritin and alveolar-arterial oxygen gradient were independent prognostic factors of poor outcome. The survival rate 24 weeks after beginning of treatment was significantly lower in those with a ferritin level of ≥ 600 ng/ml and alveolar-arterial oxygen gradient of ≥ 45 Torr (P<0.001 and P<0.001, respectively. All patients with both prognostic factors died, and the outcome was significantly poorer in these patients than in those with one or neither of the prognostic factors (P<0.001. CONCLUSIONS: We identified pre-treatment high serum ferritin level and high alveolar-arterial oxygen gradient as poor prognostic factors in DM-A/SIP patients undergoing early CSA/GC combination therapy and showed that the outcomes were poor in patients with both factors.

  13. Appreciating Oxygen

    Science.gov (United States)

    Weiss, Hilton M.

    2008-01-01

    Photosynthetic flora and microfauna utilize light from the sun to convert carbon dioxide and water into carbohydrates and oxygen. While these carbohydrates and their derivative hydrocarbons are generally considered to be fuels, it is the thermodynamically energetic oxygen molecule that traps, stores, and provides almost all of the energy that…

  14. Oxygen transfer from an intramolecularly coordinated diaryltellurium oxide to acetonitrile. Formation and combined AIM and ELI-D analysis of a novel diaryltellurium acetimidate.

    Science.gov (United States)

    Mallow, Ole; Bolsinger, Jens; Finke, Pamela; Hesse, Malte; Chen, Yu-Sheng; Duthie, Andrew; Grabowsky, Simon; Luger, Peter; Mebs, Stefan; Beckmann, Jens

    2014-08-01

    The reaction of the intramolecularly coordinated diaryltellurium(IV) oxide (8-Me2NC10H6)2TeO with acetonitrile proceeds with oxygen transfer and gives rise to the formation of the novel zwitterionic diaryltelluronium(IV) acetimidate (8-Me2NC10H6)2TeNC(O)CH3 (1) in 57% yield. Hydrolysis of 1 with hydrochloric acid affords acetamide and the previously known diarylhydroxytelluronium(IV) chloride [(8-Me2NC10H6)2Te(OH)]Cl.

  15. 高压氧联合盐酸多奈哌齐治疗卒中后认知功能障碍%Hyperbaric Oxygen Combined with Donepezil Hydrochloride in the Treatment of Post-Stroke Cognitive Impair-ment

    Institute of Scientific and Technical Information of China (English)

    许颖; 杨坚; 高宁沁; 陈小平

    2015-01-01

    目的:分析高压氧联合盐酸多奈哌齐对卒中后认知功能障碍的疗效。方法:将90例住院治疗的卒中后认知功能障碍患者分为高压氧联合盐酸多奈哌齐10 mg组、盐酸多奈哌齐10 mg组、盐酸多奈哌齐5 mg组,每组各30例。采用简易精神状态量表(MMSE)及日常生活能力量表(ADL)评价3组患者治疗前后的认知功能。结果:高压氧联合盐酸多奈哌齐10 mg组患者治疗后MMSE和ADL评分较单用盐酸多奈哌齐组明显增加,差异有统计学意义(P<0.01)。结论:高压氧联合盐酸多奈哌齐(10 mg )对卒中后伴认知功能障碍患者的疗效较好。%Objective:To analyze the efficacy of hyperbaric oxygen combined with donepezil hydrochloride on post‐stroke cogni‐tive impairment .Methods:Ninety hospitalized patients with post‐stroke cognitive impairment were selected .They were divided into hyperbaric oxygen combined with donepezil hydrochloride 10 mg group ,donepezil hydrochloride 10 mg group and donepezil hydrochloride 5 mg group ,with 30 cases in each group .Cognitive functions in 3 groups before and after the treatment were e‐valuated with the mini mental state examination (MMSE) and the ability of daily living scale (ADL) .Results:The scores of MMSE and ADL of patients in hyperbaric oxygen combined with donepezil hydrochloride 10 mg group increased more than those in donepezil hydrochloride groups after treatment ,and the differences were statistically significant (P<0 .01) .Conclu‐sions:Hyperbaric oxygen combined with donepezil hydrochloride 10 mg shows superior efficacy on post‐stroke patients accom‐panied by cognitive impairment .

  16. 电针配合高压氧治疗脑卒中偏瘫患者50例%Electro- acupuncture combined hyperbaric oxygen treating hemiplegia after stroke in 50 cases

    Institute of Scientific and Technical Information of China (English)

    张志刚; 孙毓

    2003-01-01

    BACKGROUND:Motor obstacle of limbs directly resulted from hemiplegia after stroke seriously affect patients′ daily work and living.Conventional medicine treatment can improve the function of hemiplegic limbs at some degree, but more and more studies confirm that conventional acupuncture therapy is an effective method to improve motor function of limbs.By point stimulating channel system, acupuncture therapy can regulate qi and smooth channel system, thus regulate whole body to achieve the goal of curing hemiplegia. Acupuncture combined with hyperbaric oxygen therapy can accelerate regeneration of cerebral cells, and promote the recovery of motor function of paralyzed limbs.

  17. Combined oxygen- and carbon-isotope records through the Early Jurassic: multiple global events and two modes of carbon-cycle/temperature coupling

    DEFF Research Database (Denmark)

    Hesselbo, Stephen P.; Korte, Christoph

    2010-01-01

    The Jurassic comprises some 55 million years of Earth history. However, within the Jurassic, only one major environmental change (hyperthermal) event is really well known - the Early Toarcian Oceanic Anoxic Event (OAE) at ~183 Ma - and until very recently the extent to which the accompanying...... environmental changes were global has been strongly debated. Nevertheless, partly as a result of the international effort to define Global Stratotype Sections and Points (GSSPs), much more is now being discovered about environmental changes taking place at and around the other Jurassic Age (Stage) boundaries......, to the extent that meaningful comparisons between these events can begin to be made. Here we present new carbon and oxygen isotope data from mollusks (bivalves and belemnites) and brachiopods collected through the marine Early Jurassic succession of NE England, including the Sinemurian-Plienbachian boundary...

  18. 不同供氧流量对新生儿头罩吸氧的吸入氧浓度和动脉血二氧化碳分压的影响%Oxygen concentration analyzer combines with blood gas analysis to lead the choice of oxygen flow with oxygen hood for the newborn

    Institute of Scientific and Technical Information of China (English)

    宋才好; 何燕

    2012-01-01

    目的 检测新生儿头罩吸氧时不同供氧流量下患儿血液中二氧化碳分压(PaCO2)与吸入氧浓度(FIO2)的变化关系,分析得出新生儿安全头罩用氧的规律.方法 调节氧气流量,测定在不同流量下新生儿头罩内FIO2.结果 氧气流量在3 L/min以下时,3组FIO2均小于35%,中小号头罩组有CO2潴留;氧流量在3~5 L/min时,中小号头罩组FIO2为35%左右,大号头罩组FIO2接近30%,小号头罩组有CO2潴留;氧流量在5~7 L/min时,中小头罩组FIO2为40%~50%,大号头罩组FIO2接近40%,3组均无CO2潴留;氧流量大于7 L/min时,3组FIO2均在50%以上,无CO2潴留.结论 纯氧下,选择流量在3~5 L/min,选择大中号头罩吸氧相对安全.对于没有空氧混合仪及氧浓度检测设备的基层医院进行氧气治疗有一定指导作用.%Objective By monitoring the relationship of change between pressure of carbon dioxide ( Paco2 ) and inspired oxygen concentration ( Fio2 ) when the newborn oxygen hood with different flow of oxygen, to analyze and obtain laws of newborn s safe oxygen hood. Methods The oxygen flow rate was adjusted, Fio, and Paco, in the hood under different oxygen flow were measured. Results When oxygen flow was under 3L/MIN, Fio2 of the all three groups was less than 35% , and medium and small hood groups had CO2 retention; when oxygen flow was between 3 -5L/MIN, the Fio2 of medium and small hood groups was around 35% and Fio2 of large hood group was close to 30% , and small group hood had CO2 retention; when oxygen flow was between 5 - 7L/MIN, the Fio, of medium and small hood groups was 40 -50% while the large hood group was close to 40% , and three groups had no CO2 retention; when oxygen flow was greater than 7L/MIN, the Fio2 of three groups was above 50% , without CO2 retention. Conclusion When pure oxygen is used, the oxygen flow is between 3 - 5L/ MIN, selection of the large and medium oxygen hood is relatively safe. It plays a guiding role for primary

  19. 高压氧协同药物综合治疗急性亚硝酸盐中毒9例分析%Clinical Study of Hyperbaric Oxygen Combined Therapy for 9 Cases of Acute Poisoning by Nitrite

    Institute of Scientific and Technical Information of China (English)

    林琳; 钱培丽; 朱彩琴; 赵迎春

    2012-01-01

    目的 探讨0.25 MPa高压氧(HBO)协同药物综合治疗急性亚硝酸盐中毒的疗效,通过分析急性亚硝酸盐中毒的机制明确高压氧综合治疗的临床意义.方法 0.25 Mpa HBO协同清水洗胃催吐、药物(特效解毒剂亚甲蓝拮抗、维生素C注射液、葡萄糖补液)综合治疗9例中度急性亚硝酸盐中毒患者.根据患者病情,分别给予亚甲蓝40 mg或80mg静推,维生素C3.0~5.0g静滴,HBO 1次/d,疗程1~2次.结果 9例中度急性亚硝酸中毒患者全部治愈.结论 0.25 MPa HBO协同药物综合治疗中度急性亚硝酸盐中毒患者有效.临床上除正确应用亚甲蓝等药物外,对病情较严重者应尽早高压氧治疗.%Objective To study the effect of 0.25 MPa hyperbaric oxygen therapy combined drugs for acute poisoning by nitrite. Through analyzing the mechanism of acute poisoning by nitrite, it would identify clinical significance of hyperbaric oxygen combined therapy. Methods 9 cases of midrange acute poisoning by nitrite were treated with 0.25 MPa HBO combined gastric lavage and drug therapy (methylthioninium chloride, vitamin C, glucose). Methylthioninium chloride was effective antidote of acute poisoning by nitrite. According to the patients' condition,infusion methylthioninium chloride 40 mg or 80 mg and vitamin C 3.0 -5.0 g were given intravenous,and HBO once a day,one or two as a course of treatmeat. Results 9 cases of midrange acute poisoning by nitrite treating with hyperbaric oxygen combined therapy were cured. Conclusion HBO combined therapy for midrange acute poisoning by nitrite was effective. Midrange and severe patients of acute poisoning by nitrite should be treated with HBO in early stage of the disease.

  20. Oxygen Therapy

    Science.gov (United States)

    ... oxygen at very high altitudes (like in the mountains or in an airplane) even if you do ... Med Vol 171. P1-P2, 2005 ATS Patient Education Series © 2016 American Thoracic Society www. thoracic. org ...

  1. 典型增氧设备在养殖池塘中组合应用的研究%Research on combined application of typical oxygen equipments in aquaculture ponds

    Institute of Scientific and Technical Information of China (English)

    顾海涛; 何雅萍; 王贤瑞

    2013-01-01

    叶轮式、水车式、射流式和曝气式增氧机是目前我国池塘养殖使用的主要增氧设备;由于结构形式和工作原理的不同,4种形式的增氧机有不同的特点和功能。为提高养殖池塘增氧设备的增氧效果,通过增氧设备对养殖池塘水体不同深度增氧效果的试验和养殖池塘自然增氧的试验,分析了4种典型的增氧设备的增氧性能和特点,提出了叶轮式增氧机与耕水机、水车式增氧机与耕水机、水车式增氧机与射流式增氧机以及曝气增氧机与耕水机组合配置使用的混合增氧模式,可以优势互补,充分发挥各种形式增氧设备功能。通过组合使用,达到对养殖池塘水体最大限度的增氧效果的目的。%In order to improve the oxygen effect of aeration equipment in aquaculture pond , through texts of different oxygen equipment effects on aquaculture pond water at different depths and oxygen on the effect of natural aeration pond experiment .Propounds , with the use of different aerators can give full use of the functions of different oxygen equipments , such as Impeller aerator and farming water machine , paddlewheel aerators and farming water machine , paddlewheel aerators and jet aerator , aeration machines and farming water machine . Used in combination for the objectives of achieving the maximum oxygen , and discovered a new way for improving the level of machinery of equipment ponds , aquaculture ponds utilization and unit of production .

  2. Structure, ligands and substrate coordination of the oxygen-evolving complex of photosystem II in the S2 state: a combined EPR and DFT study.

    Science.gov (United States)

    Lohmiller, Thomas; Krewald, Vera; Navarro, Montserrat Pérez; Retegan, Marius; Rapatskiy, Leonid; Nowaczyk, Marc M; Boussac, Alain; Neese, Frank; Lubitz, Wolfgang; Pantazis, Dimitrios A; Cox, Nicholas

    2014-06-28

    The S2 state of the oxygen-evolving complex of photosystem II, which consists of a Mn4O5Ca cofactor, is EPR-active, typically displaying a multiline signal, which arises from a ground spin state of total spin ST = 1/2. The precise appearance of the signal varies amongst different photosynthetic species, preparation and solvent conditions/compositions. Over the past five years, using the model species Thermosynechococcus elongatus, we have examined modifications that induce changes in the multiline signal, i.e. Ca(2+)/Sr(2+)-substitution and the binding of ammonia, to ascertain how structural perturbations of the cluster are reflected in its magnetic/electronic properties. This refined analysis, which now includes high-field (W-band) data, demonstrates that the electronic structure of the S2 state is essentially invariant to these modifications. This assessment is based on spectroscopies that examine the metal centres themselves (EPR, (55)Mn-ENDOR) and their first coordination sphere ligands ((14)N/(15)N- and (17)O-ESEEM, -HYSCORE and -EDNMR). In addition, extended quantum mechanical models from broken-symmetry DFT now reproduce all EPR, (55)Mn and (14)N experimental magnetic observables, with the inclusion of second coordination sphere ligands being crucial for accurately describing the interaction of NH3 with the Mn tetramer. These results support a mechanism of multiline heterogeneity reported for species differences and the effect of methanol [Biochim. Biophys. Acta, Bioenerg., 2011, 1807, 829], involving small changes in the magnetic connectivity of the solvent accessible outer MnA4 to the cuboidal unit Mn3O3Ca, resulting in predictable changes of the measured effective (55)Mn hyperfine tensors. Sr(2+) and NH3 replacement both affect the observed (17)O-EDNMR signal envelope supporting the assignment of O5 as the exchangeable μ-oxo bridge and it acting as the first site of substrate inclusion.

  3. Ocean circulation and freshwater pathways in the Arctic Mediterranean based on a combined Nd isotope, REE and oxygen isotope section across Fram Strait

    Science.gov (United States)

    Laukert, Georgi; Frank, Martin; Bauch, Dorothea; Hathorne, Ed C.; Rabe, Benjamin; von Appen, Wilken-Jon; Wegner, Carolyn; Zieringer, Moritz; Kassens, Heidemarie

    2017-04-01

    The water masses passing the Fram Strait are mainly responsible for the exchange of heat and freshwater between the Nordic Seas and the Arctic Ocean (the Arctic Mediterranean, AM). Disentangling their exact sources, distribution and mixing, however, is complex. This work provides new insights based on a detailed geochemical tracer inventory including dissolved Nd isotope (εNd), rare earth element (REE) and stable oxygen isotope (δ18O) data along a full water depth section across Fram Strait. We find that Nd isotope and REE distributions in the open AM primarily reflect lateral advection of water masses and their mixing. Seawater-particle interactions exert important control only above the shelf regions, as observed above the NE Greenland Shelf. Advection of northward flowing warm Atlantic Water (AW) is clearly reflected by an εNd signature of -11.7 and a Nd concentration ([Nd]) of 16 pmol/kg in the upper ∼500 m of the eastern and central Fram Strait. Freshening and cooling of the AW on its way trough the AM are accompanied by a continuous change towards more radiogenic εNd signatures (e.g. -10.4 of dense Arctic Atlantic Water). This mainly reflects mixing with intermediate waters but also admixture of dense Kara Sea waters and Pacific-derived waters. The more radiogenic εNd signatures of the intermediate and deep waters (reaching -9.5) are mainly acquired in the SW Nordic Seas through exchange with basaltic formations of Iceland and CE Greenland. Inputs of Nd from Svalbard are not observed and surface waters and Nd on the Svalbard shelf originate from the Barents Sea. Shallow southward flowing Arctic-derived waters (freshwater of up to ∼6%. In addition to these observations, this study shows that the pronounced gradients in εNd signatures and REE characteristics in the upper water column provide a reliable basis for assessments of shallow hydrological changes within the AM.

  4. 高压氧并盐酸多奈哌齐治疗血管性痴呆的疗效观察%Hyperbaric oxygen combined with donepezil in the treatment of vascular dementia

    Institute of Scientific and Technical Information of China (English)

    王水平; 陶珍; 丁素菊; 程晋成; 余本松; 王轶群

    2009-01-01

    目的 观察高压氧(HBO)并盐酸多奈哌齐治疗血管性痴呆(VD)的效果.方法 将64例VD患者随机分为观察组和对照组,每组32例.观察组用HBO并盐酸多奈哌齐治疗,对照组单用盐酸多奈哌齐治疗,均治疗12周,治疗前、后2组均采用简易精神状态量表(MMSE)及长谷川痴呆量表(HDS)进行评定.结果 观察组及对照组治疗后MMSE、HDS分数均有明显提高,差异有统计学意义(P<0.05);观察组改善情况明显优于对照组,两者比较差异有统计学意义(P<0.05).结论 HBO并用盐酸多奈哌齐治疗VD效果更佳.%Objective To investigate the efficacy of hyperbaric oxygen combined with donepezil in the treat-ment of patients with vascular dementia(VD). Methods Sixty-four patients with VD were randomly divided into a control group(donepezil group,n=32)and a treatment group(hyperbaric oxygen combined with donepezil,n=32).The course of treatment was 12 weeks.All patients were tested using the Mini-Mental State Examination(MMSE)and Hasegawa's dementia scale(HDS)before and after treatment. Results After 12 weeks of treatment,the MMSE scores and HDS scores of patients increased significantly in both the control and treatment groups.There were signifi-cant differences between the control and treatment groups in terms of MMSE and HDS scores.Conclusion Hyperbar-ic oxygen combined with donepezil could significantly improve cognition in VD patients.

  5. 负压封闭引流联合氧气治疗压疮创面细菌量研究%Study on bacterial count in pressure ulcers treated by VSD combined with oxygen therapy

    Institute of Scientific and Technical Information of China (English)

    张斌; 任海鹏; 任传成; 陈刚; 李海龙; 陈敏; 杨涛; 杨义明; 朱振安

    2015-01-01

    目的:探讨负压封闭引流(VSD)联合氧气治疗压疮对创面组织细菌量的影响。方法选择压疮患者60例,随机分为两组,对照组采取 VSD 治疗,观察组采用 VSD 治疗为主,并辅以间断高浓度氧气治疗。对两组治疗前后的疗效及创面细菌量进行对比分析。结果观察组治疗后总有效率为83.33%,明显高于对照组的总有效率(53.33%),差异有统计学意义(P<0.05)。两组患者在治疗前的创面组织细菌量差异无统计学意义(P>0.05),观察组在治疗1、3、7、10 d 后创面组织细菌量均显著低于对照组,差异有统计学意义(P<0.01)。结论 VSD 联合氧气治疗对压疮创面感染的防治效果良好。%Objective To investigate the influence of vacuum sealing drainage(VSD )combined with oxygen therapy for treating pressure ulcers on bacterial count .Methods 60 patients with pressure ulcer in our hospital were selected and randomly divided into two groups .The control group adopted the VSD therapy ,while the observation group received VSD combined with interrupted high concentration oxygen therapy .The treatment effects and bacteri‐al count of wound surface were comparatively analyzed .Results The total effective rate after treatment in the obser‐vation group was 83 .33% ,which was significantly higher than 53 .33% in the control group ,the difference was sta‐tistically significant(P 0 .05) ,the bacterial count on 1 ,3 ,7 ,10 d of treatment in the observation group were sig‐nificantly lower than those in the control group ,the differences were statistically significant(P< 0 .01) .Conclusion VSD combined with oxygen therapy has better effect for preventing wound infection of pressure ulcer .

  6. Effect of combination of oxygen, ozone and VSD in healing traumatic wound surface%氧、臭氧及负压封闭引流联合应用对创面的治疗作用

    Institute of Scientific and Technical Information of China (English)

    黄显凯; 王韬; 朱渝军

    2011-01-01

    目的 探讨联合应用负压封闭引流、局部氧疗及臭氧治疗对创伤创面的治疗作用.方法 选择2009年8月~2010年9月期间收治的50例胸腹壁、背部、四肢严重皮肤及软组织损伤病人,男性30例,女性20例;年龄16~58岁,平均35.8岁.平均创面面积124.5cm2.清创后30例采用氧、臭氧及负压封闭引流综合治疗(简称综合组):20例按常规方法换药(常规组).观察综合治疗和常规治疗对创伤性创面愈合的细菌及组织学变化影响.结果 综合组创面愈合时间及创面植皮时间均较常规组明显缩短(P<0 05);综合治疗组第5、7天创面细菌数显著低于常规组(P<0.01).光镜下观察综合治疗组肌纤维水肿程度较轻,炎性细胞浸润及血管扩张充血均较常规组轻.结论 联合应用负压封闭引流、局部氧疗及臭氧治疗可以优势互补,显著提高皮肤及软组织创面的治疗效果.%Objective To investigate the therapeutical effect of combination of oxygen, ozone and VSD on traumatic wound surface. Methods We studied fifty patients with severe skin and soft tissue injury in thoracic and abdominal wall,back and limbs,who admitted to our hospital from Aug. 2009 to Sep. 2010. There were 30 males and 20 females,aging from 16 to 58 ( average 35.8 ) years. The mean area of wound surface was 124.5cm2. Thirty patients(the combined therapy group) were debrided in common way and disposed by combined therapy of oxygen,ozone and VSD. While the other 20 patients ( the routine therapy ) were treated with the routine disposal. The effect of hemostasis and healing on wound surface was observed. Results The healing time and skin grafting time of the wound surface in the combined therapy group were all shortened apparently in contrast with the routine group (P <0. 05 ). The bacterial number of the wound surface in the combined therapy group in the 5th and 7th day ( P <0. 01) was remarkably less than the routine group. Under light

  7. Vibrational spectrum and structure of CoO6: a model compound for molecular oxygen reversible binding on cobalt oxides and salts; a combined IR matrix isolation and theoretical study.

    Science.gov (United States)

    Marzouk, Asma; Danset, Delphine; Zhou, Ming Fei; Gong, Yu; Alikhani, Mohammad E; Manceron, Laurent

    2011-08-18

    The formation and structure of a novel species, a disuperoxo-cobalt dioxide complex (CoO(6)), has been investigated using matrix isolation in solid neon and argon, coupled to infrared spectroscopy and by quantum chemical methods. It is found that CoO(6) can be formed by successive complexation of cobalt dioxide by molecular oxygen without activation energy by diffusion of ground state O(2) molecules at 9K in the dark. The IR data on one combination and seven fundamentals, isotopic effects, and quantum chemical calculations are both consistent with an asymmetrical structure with two slightly nonequivalent oxygen ligands complexing a cobalt dioxide subunit. Evidence for other, metastable states is also presented, but the data are not complete. The electronic structure and formation pathway of this unique, formally +VI oxidation state, complex has been investigated using several functionals of current DFT within the broken-symmetry unrestricted formalism. It has been shown that the M06L pure local functional well reproduce the experimental observations. The ground electronic state is predicted to be an open shell (2)A'' doublet with the quartet states above by more than 9 kcal/mol and the sextet lying even higher in energy. The ground state has a strong and complex multireference character that hinders the use of more precise multireference approaches and requires caution in the methodology to be used. The geometrical, energetic, and vibrational properties have been computed.

  8. 水氧联合丹参酮胶囊治疗中重度痤疮的疗效观察%To Observe the Curative Effect of Acne about Using the Water Oxygen Combined Oral Tanshinone Capsule

    Institute of Scientific and Technical Information of China (English)

    房武宁

    2015-01-01

    Objective To observe the curative ef ect of acne about using the water oxygen combined oral tanshinone capsule.Methods Selected 88 cases of patients with moderately severe acne in the hospital dermatology clinic.Randomly divided into treatment group and control group.The treatment group treated with water oximeter and tanshinone capsule and control group used tanshinone capsule. Observed their curative ef ect after 2 months.Results Treatment group total ef ective rate was 88.64%,obviously much higher than the control group of 70.45%.The dif erence had statistical significance ( <0.05).Conclusion The curative ef ect of acne about using the water oxygen combined oral tanshinone capsule is remarkable.%目的观察水氧联合口服丹参酮胶囊治疗中重度痤疮的疗效。方法选取我院皮肤科门诊就诊的88例中重度痤疮患者,随机平分为两组,其中治疗组44例予水氧仪治疗联合口服丹参酮胶囊。对照组44例予丹参酮胶囊口服,治疗2个月后观察并对比其疗效。结果治疗组总有效率为88.64%,明显比对照组中的70.45%要高得多,其差异具有统计学上的意义(<0.05)。结论水氧联合丹参酮胶囊治疗中重度痤疮疗效较显著。

  9. 高压氧联合药物治疗突发性耳聋临床对比研究%Hyperbaric Oxygen Combined With Drug Treatment of Sudden Deafness

    Institute of Scientific and Technical Information of China (English)

    王栋武

    2015-01-01

    目的:重点探索高压氧联合药物应用于治疗突发性耳聋的有效性。方法挑选的研究对象是86例突发性耳聋患者,将患者分成两组,采用不同的方法治疗。结果对照组的有效率仅仅达到74.42%,显著低于观察组的97.67%。对照组的满意度较低,仅可达到72.09%,显著低于观察组的97.67%。结论高压氧联合药物应用于治疗突发性耳聋的有效性较高,值得推荐。%Objective To explore the effectiveness of hyperbaric oxygen combined with the focus of drug used in the treatment of sudden deafness. Methods The subjects were selected 86 cases of sudden deafness patients, the patients were divided into two groups, using different methods of treatment. Results The response rate in the control group reached only 74.42 percent, signiifcantly lower than the 97.67%in the observation group. Lower satisfaction with the control group, only up to 72.09%, signiifcantly lower than the 97.67% in the observation group. Conclusion The high effectiveness of hyperbaric oxygen combined with drugs used in the treatment of sudden deafness, is recommended.

  10. Combined effect of an oxygen absorber and oregano essential oil on shelf life extension of rainbow trout fillets stored at 4 degrees C.

    Science.gov (United States)

    Mexis, S F; Chouliara, E; Kontominas, M G

    2009-09-01

    In the present study the combined effect of an O2 absorber and oregano essential oil (0.4% v/w) on shelf life extension of rainbow trout fillets (Onchorynchus mykiss) stored under refrigeration (4 degrees C) was investigated. The study was based on microbiological [TVC, Pseudomonas spp., Lactic Acid Bacteria, H2S-producing bacteria including Shewanella putrefaciens, Enterobacteriaceae and Clostridium spp.), physicochemical (pH, PV, TBA, TVBN and Drip loss) and sensory (odor, taste) changes occurring in the product as a function of treatment and storage time. Aerobically-packaged rainbow trout fillets stored at 4 degrees C were taken as control samples. Results showed that TVC exceeded 7 log cfu/g on day 4 of storage for control samples, day 7-8 for samples containing oregano oil, day 9 for samples containing the O2 absorber and day 12-13 for samples containing the O2 absorber and oregano oil. Pseudomonas spp., Enterobacteriaceae and LAB were only partially inhibited by the O2 absorber and/or the oregano oil. In all cases the inhibition effect was more pronounced when the combination of O2 absorber with oregano essential oil was used. pH decreased from an initial value of 6.65-6.09 and subsequently increased to 6.86 due to formation of protein decomposition products. % Drip loss ranged between 7% and 11-12% at the end of the product shelf life. PV values ranged between 11.4 and 27.0 meq O2/kg oil while malondialdehyde (MDA) ranged between 9.6 and 24.5 mg/kg. TVBN ranged between 10.6 and 54.6 mg/kg at the time of sensory rejection. Sensory shelf life was 4 days for the control samples, 7-8 days for samples containing oregano oil, 13-14 days for samples containing the O2 absorber and 17 days for samples containing the O2 absorber plus oregano oil.

  11. 依帕司他联合高压氧治疗早期糖尿病肾病的临床观察%Clinical observation on early diabetic nephropathy treated with epalrestat combined hyperbaric oxygen

    Institute of Scientific and Technical Information of China (English)

    黄锦欢; 孙鹏飞; 覃灿彬; 赖海春; 张俊林

    2012-01-01

    Objective To observe the effects of combined therapy of epalrestat and hyperbaric oxygen on urinary albumin excretion rate of early diabetic nephropathy. Methods 78 patients with early type 2 diabetic nephropathy were randomly divided into treated group and control group (39 cases each). Control group was treated with insulin and epalrestat, and treated group was treated with insulin, epalrestat and hyperbaric oxygen. The course last 2 months. Blood glucose, lipids, blood rheology and urinary albumin excretion rate ( UAER) were detected before and after treatment. Results There were no differences between 2 groups in blood glucose and lipid before or after treatment (P >0. 05 ). UAER was decreased in both groups as compared to before treatment. But there was significantly difference between 2 groups in UAER after treatment (P<0. 05). Conclusion The combined therapy of epalrestat and hyperbaric oxygen reduces UAER, thus inhibiting the progress of early diabetic kidney disease, the therapy is more effective than epalrestat alone.%目的 观察依帕司他联合高压氧治疗对早期糖尿病肾病尿白蛋白排泄率的影响.方法 将78例早期2型糖尿病肾病患者随机分为治疗组和对照组(各39例),两组均予胰岛素控制血糖,并予依帕司他口服,在此基础上,治疗组加予高压氧治疗,疗程2个月,治疗前后检测血糖、血脂、血液流变学及尿白蛋白排泄率(UAER).结果 治疗前后两组患者血糖、血脂等比较,差异无统计学意义(P>0.05);治疗后两组UAER均下降,但治疗组下降更加显著,两组比较差异有统计学意义(P<0.05).结论 依帕司他联合高压氧可有效降低尿白蛋白排泄率,从而抑制早期糖尿病肾病的进展,疗效优于单纯药物治疗.

  12. Analysis on effect of hyperbaric oxygen combined with psychological nurs-ing intervention for patients with traumatic brain%颅脑损伤患者高压氧联合心理护理干预效果分析

    Institute of Scientific and Technical Information of China (English)

    杨艳; 张禹; 肖宏

    2015-01-01

    Objective To investigate the effect of hyperbaric oxygen combined with psychological nursing intervention for patients with traumatic brain. Methods From July to November 2014, 62 cases of the patients with traumatic brain injury in Beijing Navy General Hospital were randomly divided into observation group and control group, each group had 31 cases. Both groups were given hyperbaric oxygen treatment and hyperbaric oxygen routine care, based on these, the observation group was added to psychological care. Glasgow coma scale score (GCS) was used to assess the im-provement of patient's consciousness, barthel index (BI) was used to assess the prognosis of the patients, self-rating scale (SAS) and self-rating depression scale (SDS) was used to analyze patients' mental disorder, and patients satisfac-tion with care was evaluated. The results of the two groups were compared. Results①GCS score [(5.41±1.22) v s (5.49±1.24) points] of the observation group and control group two days before hyperbaric oxygen therapy was compared, there was no significant difference (t=1.24, P>0.05);GCS score [(7.78±1.56) vs (6.57±1.54)points] of the observation group and control group two weeks after hyperbaric oxygen therapy was compared, GCS score [(12.01±2.46) vs (8.31±1.93) points] of the observation group and control group eight weeks after hyperbaric oxygen therapy was compared, there were significant differences (t = 6.33, P0.05);高压氧治疗2周[(7.78±1.56)比(6.57±1.54)分]、8周[(12.01±2.46)比(8.31±1.93)分]比较,差异有统计学意义(t=6.33,P<0.05;t=12.41,P<0.01)。②两组患者治疗24周后,预后情况观察组优于对照组(字2=13.31,P<0.05)。③心理干预(高压氧治疗8周时)后,观察组焦虑评分[(44.38±2.47)分]低于对照组[(53.54±2.83)分],差异有统计学意义(t=5.20,P<0.05);观察组抑郁评分[(39.46±2.51)分]低于对照组[(47.62±2.16)分],差异有统计学意义(t=6.46,P<0.05)。榆观察组患者护理

  13. Oxygen isotope dynamics of atmospheric nitrate over the Antarctic plateau: First combined measurements of ozone and nitrate 17O-excess (Δ17O)

    Science.gov (United States)

    Vicars, William; Savarino, Joël; Erbland, Joseph; Preunkert, Susanne; Jourdain, Bruno; Frey, Markus; Gil, Jaime; Legrand, Michel

    2013-04-01

    Variations in the isotopic composition of atmospheric nitrate (NO3-) provide novel indicators for important processes in boundary layer chemistry, often acting as source markers for reactive nitrogen (NOx = NO + NO2) and providing both qualitative and quantitative constraints on the pathways that determine its fate. Stable isotope ratios of nitrate (δ15N, δ17O, δ18O) offer direct insight into the nature and magnitude of the fluxes associated with different processes, thus providing unique information regarding phenomena that are often difficult to quantify from concentration measurements alone. The unique and distinctive 17O-excess (Δ17O = δ17O - 0.52 × δ18O ) of ozone (O3), which is transferred to NOx via oxidation reactions in the atmosphere, has been found to be a particularly useful isotopic fingerprint in studies of NOx transformations. Constraining the propagation of 17O-excess within the NOx cycle is critical in polar areas where there exists the possibility of extending atmospheric interpretations to the glacial/interglacial time scale using deep ice core records of nitrate. Here we present measurements of the comprehensive isotopic composition of atmospheric nitrate collected at Dome C, Antarctica during December 2011 to January 2012. Sampling was conducted within the framework of the OPALE (Oxidant Production over Antarctic Land and its Export) project, thus providing an opportunity to combine our isotopic observations with a wealth of meteorological and chemical data, including in-situ concentration measurements of the gas-phase precursors involved in nitrate production (NOx, O3, OH, HO2, etc.). Furthermore, nitrate isotope analysis has been combined in this study for the first time with parallel observations of the transferrable Δ17O of surface ozone, which was measured concurrently at Dome C using our recently developed analytical approach. This unique dataset has allowed for a direct comparison of observed Δ17O(NO3-) values to those that are

  14. 高压氧联合糖皮质激素治疗难治性突发性聋疗效观察%Therapeutic effects of hyperbaric oxygen combined with glucocorticoid on refractory idiopathic sudden deafness

    Institute of Scientific and Technical Information of China (English)

    杨晨; 张禹; 李航; 孟祥恩; 潘树义

    2014-01-01

    目的 观察高压氧(hyperbaric oxygen,HBO)联合糖皮质激素(glucocorticoid,GC)对难治性突发性聋临床疗效.方法 经患者知情同意,并经医院伦理委员会批准,根据患者是否使用GC治疗,将有完整临床资料的79例突发性聋患者分为HBO联合GC治疗组44例,单纯HBO组35例.另外,在我院同期耳鼻喉科收治的复诊就医的突发聋患者中,选取使用GC治疗但未进行HBO治疗患者32例,作为单纯GC组.通过分析治疗有效率、治愈率和听力改善率,对比联合治疗与单纯HBO治疗及单纯GC药物治疗的疗效差异.结果 HBO联合GC组患者的治疗有效率(59.52%)和听力改善率[(61.3±14.7)%]明显高于单纯HBO组[28.13%,(43.6±5.5)%]和单纯GC组[31.25%,(56.4±4.1)%].结论 对难治性突发性聋HBO联合GC较单纯HBO治疗或GC治疗效果更好.%Objective Observe the therapeutic effects of hyperbaric oxygen (HB0) combined with glucocorticoid (GC) on refractory idiopathic sudden deafness.Methods Forty-two patients with sudden deafness (refractory idiopathic sudden deafness),who failed to recover after over one month of onset,were admitted into our Center from 2010 to 2013 for treatment with HBO combined with GC (referred to as the combined treatment group).Another 2 groups of patients with refractory idiopathic sudden deafness (each consisting of 32 patients),who were admitted into either our Center or the Department of Otorhinolaryngology of the Navy General Hospital and treated with simple HBO or GC,were used as controls.Through analyses of effective rates,cure rates and improvement rates in hearing,differences in therapeutic effects were compared between the patient group treated with HB0 combined with GC and the 2 control groups.Results The effective rate (59.52%) and improvement rate [(61.3 ± 4.7)%] for the combined treatment group were obviously higher than those of the simple HBO group[28.13%,(43.6 ± 5.5)%] and the simple hormone group [31.25

  15. 尼麦角林联合高压氧治疗血管性认知功能障碍疗效观察%Efficacy of nicergline combined with hyperbaric oxygen treatment on vascular cognitive impairment

    Institute of Scientific and Technical Information of China (English)

    陈国军; 张燕柳; 张惠莉; 于永娜; 宋帅召

    2015-01-01

    目的 探讨尼麦角林联合高压氧治疗血管性认知功能障碍(VCI)的疗效.方法 选取血管性认知功能障碍患者120例,随机分为尼麦角林治疗组40例,高压氧治疗组40例,联合治疗组40例,疗程共8周,以简易精神状态检查表(MMSE)、韦克斯勒记忆量表(WMS)和日常生活能力量表(ADL)为评价指标,评价3组患者的疗效.结果 3组患者临床资料比较差异无统计学意义(均P>0.05),具有可比性.经8周治疗干预后,联合治疗组MMSE、WMS、ADL较治疗前均有改善(P<0.01).尼麦角林治疗组上述三项指标改善明显(P<0.05),而高压氧治疗组MMSE、ADL评分较前改善(P<0.05),联合治疗组与尼麦角林治疗组和高压氧治疗组组间比较,上述指标差异有统计学意义(P<0.05).而尼麦角林组与高压氧治疗组比较,仅MMSE差异有统计学意义.3组均无明显相关不良反应出现.结论 在血管性认知功能障碍治疗中,尼麦角林联合高压氧治疗疗效显著,患者日常生活能力和认知能力提高明显,无不良反应发生,值得在临床中推广.%Objective To investigate the efficacy of nicergoline combined with hyperbaric oxygen treatment on vascular cognitive impairment.Methods 120 patients with vascular cognitive impairment were randomly divided into 3 treatment groups:nicergoline,hyperbaric oxygen,and both treatment (n=40,each) for 8 weeks.Mini mental state examination (MMSE),Wechsler memory scale (WMS) and activities of daily living scale (ADL) were used as assessing items.The efficacy of treatment in each group was evaluated.Results There were no significant differences in clinical data among the three groups(x2=0.324,t=0.265 and 0.861,P=0.764,0.784 and 0.386).After 8 weeks of intervention,scores of MMSE,WMS and ADL were significantly improved in the combined treatment groups compared with pre-treatment (all P<0.01),and the improvements were observed in nicergoline group (all P<0.05),while only MMSE and

  16. Reversible Oxygenation of Oxygen Transport Proteins.

    Science.gov (United States)

    Drain, C. M.; Corden, Barry B.

    1987-01-01

    Describes a lecture demonstration which illustrates changes in the visible spectra of oxygen transport proteins upon reversible oxygen binding. Provides a comparison of the physical characteristics of oxygen storage and transport proteins. Reviews essentials for preparation of the materials. (ML)

  17. Changes in brain function and anatomical structure following treatment of hyperbaric oxygen for visual pathway abnormalities In 16 cases Evaluation of functional magnetic resonance Imaging combined with diffusion tensor imaging

    Institute of Scientific and Technical Information of China (English)

    Ziqian Chen; Ping Ni; Hui Xiao; Jinhua Chen; Gennian Qian; Youqiang Ye; Shangwen Xu; Jinliang Wang; Xizhang Yang

    2008-01-01

    BACKGROUND:There is a growing research focus on the combination of blood oxygenation level dependent functional magnetic resonance imaging(BOLD-fMRI)and diffusion tensor imaging(DTI)to evaluate visual cortical function and structural changes in the cerebrum,as well as morphological changes to the white matter fiber tracks,after visual pathway lesions.However,the combined application of BOLD-fMRI and DTI in treating of visual pathway abnormalities still requires further studies. OBJECTIVE:To observe and evaluate the effects of hyperbaric oxygen on visual pathway abnormalities,and to evaluate the characteristics of cerebral function and anatomic structural changes by using BOLD-fMRI combined with DTI technique. DESIGN:Case contrast observation. SETTING:Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA.PARTICIPANTS:Sixteen patients(9 males and 7 females,15-77 years old)with lateral or bilateral visual disorder induced by visual pathway lesions were selected from the Department of Neurology,Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA from January 2006 to May 2007.These patients comprised the lesion group.Measures of interventional therapy:hyperbaric oxygen of two normal atmospheres for three courses(10 d/course)and routine internal medicine treatment.In addition,12 healthy subjects of similar sex and age to the lesion group were regarded as the control group.The control group underwent routine ophthalmological and ocular fundus examinations; diagnostic results were normal. The experiment received confirmed consent from the local ethic committee,and all patients provided informed consent.METHODS:BOLD-fMRI and DTI manifestations in the lesion group were observed before and after hyperbaric oxygen intervention,and the results were compared with the control group.The subjects were positioned on their back,and BOLD-fMRI images were collected with the following GRE EPI sequence:TR= 2 000 ms,TE=40 ms,layer thickness=5 mm

  18. Hyperbaric Oxygen Therapy

    Science.gov (United States)

    ... before your first hyperbaric oxygen therapy session. During hyperbaric oxygen therapy Hyperbaric oxygen therapy typically is performed ... and the therapy unit throughout your treatment. After hyperbaric oxygen therapy You may feel somewhat tired or ...

  19. 高压氧辅助药物治疗动脉粥样硬化脑血管痉挛随机对照研究%Effect of hyperbaric oxygen combined with drug on patients with atherosclerotic cerebral vasospasm

    Institute of Scientific and Technical Information of China (English)

    辜忠灵

    2014-01-01

    目的:分析高压氧辅助药物治疗动脉粥样硬化脑血管痉挛的效果。方法选择在本院接受住院治疗的动脉粥样硬化脑血管痉挛患者作为研究对象,分别给予单纯药物治疗及高压氧辅助药物治疗,比较有效率、血液学指标、基底动脉管径及NO、NOS、Ca2+含量等。结果观察组有效率(97.06%)、基底动脉管径[(4.98±1.35)mm]、NO [(59.43±11.48)μmol/L]、NOS[(98.43±14.38)kU/L]均明显高于对照组;胆固醇[(3.12±0.72)mmol/L]、甘油三酯[(1.27±0.41)mmol/L]、血小板计数[(112.74±13.36)×109/L]、血黏度[(1.21±0.37) mPa · s]、[Ca2+(17.07±1.65)g/μmol]明显低于对照组( P<0.05)。结论高压氧辅助药物可有效提高动脉粥样硬化脑血管痉挛患者的临床疗效,优化血液学指标,升高基底动脉管径、NO及NOS ,减少Ca2+含量,具有积极的临床意义。%Objective To analyze the efficacy of hyperbaric oxygen combined with drug on patients with atherosclerotic cerebral vasospasm. Methods Patients with atherosclerotic cerebral vasospasm admitted to our hospital were chosen as re-search subjects ,and divided into observation group and control group. The control group was given drug therapy alone and the observation group was given hyperbaric oxygen combined with drug therapy. The efficiency of treatment ,hematological index , and basilar artery diameter ,NO ,NOS ,Ca2+ level of the two groups were compared. Results The efficacy rate (97.06% ) ,bas-al artery diameter(4.98 ± 4.98) mm ,NO(59.43 ± 11.48)μmol/L ,NO (98.43 ± 14.38) kU/L of observation group were sig-nificantly higher than those of the control group ;Cholesterol(3.12 ± 0.72) mmol/L ,triglycerides(1.27 ± 0.41) mmol/L , platelet count(112.74 ± 13.36)109/L ,blood viscosity(1.21 ± 0.37 )mPa · s ,Ca2+ (17.07 ± 1.65) g/μmol were significantly lower than those of the control group(P<0.05).Conclusion Hyperbaric oxygen

  20. Combination hyperbaric oxygen and temozolomide therapy in c6 rat glioma model Terapia combinada de oxigênio hiperbárico e temozomida no modelo C6 de glioma em ratos

    Directory of Open Access Journals (Sweden)

    Yaşar Dagıstan

    2012-06-01

    Full Text Available PURPOSE: Temozolomide (TMZ has anti-tumor activity in patients with malignant glioma. Hyperbaric oxygen (HBO may enhance the efficacy of certain therapies that are limited because of the hypoxic tumor microenvironment. We examined the combined effects of TMZ-HBO in a rat glioma model. METHODS: After stereotactic injection of C6/LacZ rat glioma cells into the Wistar rats brain, the rats were randomly assigned to three treatment groups [group 1, control treatment; group 2, TMZ alone; group 3, a combination of TMZ and HBO]. Rats were sacrificed 18 days after treatment, and number of intra-/peri-tumoral vessels, microendothelial proliferations, immunohistochemistry and necrotic area were evaluated. RESULTS: Tumoral tissue was stained only sparsely with GFAP. Temozolomide treatment was significantly decreased in tumor tissue intratumoral vessel number / total tumor area level. The level of Ki67 was significantly decreased in the tumor tissue of the group 3. Additionally, the total necrotic area / total tumor volume (% was decreased significantly in tumor tissue of the group 3 rats compared to group1 and 2. CONCLUSION: The combination of hyperbaric oxygen with temozolomide produced an important reduction in glioma growth and effective approach to the treatment of glioblastoma.OBJETIVO: A temozolomida (TMZ tem atividade anti-tumoral em pacientes com glioma maligno. Oxigênio hiperbárico (HBO pode aumentar a eficácia de terapias que são limitadas devido a um microambiente do tumor hipóxico. Foram examinados os efeitos combinados de TMZ-HBO em um modelo de glioma em rato. MÉTODOS: Após a injeção estereotáxica de células de glioma de rato C6/LacZ no cérebro de ratos Wistar, os ratos foram distribuídos aleatoriamente em três grupos de tratamento: Grupo 1: tratamento de controle. Grupo 2: TMZ sozinho. Grupo 3: uma combinação de TMZ e HBO. Os ratos foram sacrificados 18 dias após o tratamento. Foram avaliados o número de vasos intra

  1. Influence of hyperbaric oxygen combining Temozolomide on human glioblastoma cell line U251%高压氧联合替莫唑胺对胶质瘤U251细胞的影响

    Institute of Scientific and Technical Information of China (English)

    曹侃; 袁志诚; 陆新宇; 李慧勇

    2012-01-01

    Objective To discuss the influence and mechanism on hyperbarie oxygen ( HBO) combining Temozolomide with human glioblastoma cell line U251. Method The cells were divided into four groups,A group is HBO combining Temozolomide,B group is HBO,C group is Temozolomide and D group is control group. By simulation of hypoxia microenviroment in vitro, the rate of growth inhibiting is investigated by MTT method. The rate of cell death is observed by PI staining. The rate of apoptosis is analyzed by the flow cytometry. Elasia method is used to detect the expression of hypoxia-inducible factorl-α (HIFl-α) and Multidrug resistance-associated protein-1 ( MRP-1). Results The group of HBO combining Temozolomide is obviously higher than others in rate of growth inhibiting, rate of cell death, rate of apoptosis, the results have statistics differences(P 0. 05) , but to others it has statistics value (P < 0. 05). Conclusion HBO can enhance the chemotherapy effect of temozolomide, it can correct the hypoxic microenvironment and reduce the expression of HIFl-α and MRP-1 ,these may be the key to effect.%目的 研究高压氧( Hyperbaric Oxygen,HBO)联合替莫唑胺(Temozolomide)对人神经胶质瘤U251细胞株的的影响及其机制.方法 实验分为4组:A组高压氧联合替莫唑胺组、B组高压氧组、C组替莫唑胺组、D组对照组.通过体外模拟缺氧微环境,用四甲基偶氮唑蓝法(MTT法)、碘化丙啶(PI)染色法、流式细胞仪分别检测细胞生长抑制率、细胞死亡率、细胞凋亡率.Elisa法检测缺氧诱导因子1-α(HIF1-α)和多药耐药相关蛋白-1(MRP-1)的表达情况.结果 1高压氧联合替莫唑胺组在细胞生长抑制率、细胞死亡率和细胞凋亡率上明显高于其他组,数值均有统计学意义(P<0.05).2高压氧联合替莫唑胺组与高压氧组在HIF1-α和MRP-1上无统计学意义(P>0.05),与其他组有统计学意义(P<0.05).结论 高压氧够增强替莫唑胺化疗效果,高压氧纠

  2. 冰温结合不同比例氧气气调对冷却肉的保鲜效果%Effect of modified atmosphere package with varying oxygen concentrations combined with controlled freezing-point storage on pork fresh-keeping

    Institute of Scientific and Technical Information of China (English)

    谢晶; 李建雄; 潘迎捷

    2009-01-01

    试验研究了在冰温基础上结合不同含氧比例气调对冷却猪肉保鲜的影响,试验设置冰温、冷藏(4℃)、真空包装+冰温、20%CO_2+80%O_2(高氧)+冰温、20%CO_2+20%O_2+60%N_2(低氧)+冰温、20%CO_2+80%N_2(无氧)+冰温6个试验组,测定菌落总数、挥发性盐基氮、汁液流失率、保水能力和色差.结果表明:冰温条件下高氧和低氧的菌落总数24 d还未超过冷却肉卫生标准,且两组之间无显著差异(P>0.05);在整个贮藏期内高氧气调和低氧气调可以维持冷却肉的色泽在一个小的范围内变化;高氧气调和低氧气调8 d后汁液流失率显著高于单纯冰温和无氧气调(P<0.05),高氧气调12 d后汁液流失率显著高于低氧气调(P<0.05),同时高氧气调8 d后持水能力显著大于低氧气调(P<0.05).在冰温条件下,80%O_2和20%O_2都能长时间维护冷却肉的色泽,均能较好抑制微生物的增殖,但在汁液流失率、保水能力方面各有优势.%Effect of modified atmosphere packaging with varying oxygen concentrations combined controlled freezing-point storage on pork fresh-keeping was studied. By determining physicochemical parameters such as total plate count, total volatile base nitrogen (TVB-N), drip loss, water holding capacity and color, the qualities of pork under controlled freezing-point storage, chill storage, vacuum package+controlled freezing-point storage, 20%CO_2+80%O_2 (high oxygen)+controlled freezing-point storage, 20%CO_2+20%O_2+60%N_2 (low oxygen)+controlled freezing-point storage and 20%CO_2+80%N_2(no oxygen)+controlled freezing-point storage were compared. It showed that total plate count under high oxygen and low oxygen did not exceed the hygiene standard of pork after twenty-four days, and there was no significant difference between them(P>0.05). High oxygen modified atmosphere package(MAP) and low oxygen MAP maintained the color better. The drip losses of high oxygen MAP and low oxygen MAP after eight

  3. 高压氧联合甲钴胺治疗糖尿病周围神经病变的疗效%Effects of therapy of hyperbaric oxygen combined with mecobalamin on diabetic peripheral neuropathy

    Institute of Scientific and Technical Information of China (English)

    杨金华; 王金春; 金越

    2008-01-01

    目的 评价高压氧联合甲钴胺对糖尿病周围神经病变的疗效,探讨治疗糖尿病周围神经病变的有效方法.方法 378例糖尿病周围神经病变患者分为2组.治疗组198例,予高压氧联合甲钴胺治疗,高压氧疗法采用大型空气加压舱,治疗压力为0.2 Mpa(2.0 ATA),每日1次;甲钴胺500 μg,肌肉注射,每日1次.对照组180例,单独使用甲钴胺500 μg,肌肉注射,每日1次.2组患者疗程均为4周.结果 治疗组显效率、总有效率分别为40.9%和100%,明显高于对照组的17.3%及53.3%,2组间差异有统计学意义(P<0.01);治疗组神经传导速度及血流动力学改善均明显高于对照组(P<0.01).结论 高压氧联合甲钴胺对糖尿病周围神经病变的治疗效果显著,总有效率为100%,可作为糖尿病周围神经病变的常规治疗方法.%Objective To study effects of hyperbaric oxygen combined with mecobalamine on diabetic peripheral neuropathy(DPN)and explore effective therapeutic way to DPN.Methods Three hundred and seventy-eight patients.were divided into two groups.The treatment group(198 cases)were treated with hyperbaric oxygen(HBO)and mecobalamin(0.2 MPa,500 μg mecobalamin i.m.,once a day).The control group(180 cases)were only treated with 500 μg meeobalamin i.m.,once a day.Courses of treatment in two groups both were four weeks.Results The effective rate and overall efficacy rate of treatment group were 40.9% and 100%,respectively.They were significantly higher than those of control group(17.3% and 53.3%)(P<0.01).At the same time,there were obvious differences in nerve conduction velocity and dvnamics of blood flow between two groups(P<0.01).Conclusions HBO combined with mecobalamin has therapeutic effect on DPN,which may be regared as a conventional therapy.

  4. CLINICAL OBSERVATION OF ANTIBIOTIC IRRIGATION COMBINED WITH HYPERBARIC OXYGEN THERAPY IN THE TREATMENT OF OSTEOMYELITIS%抗生素灌洗疗法联合高压氧治疗骨髓炎的临床观察

    Institute of Scientific and Technical Information of China (English)

    潘勇泉; 刘志祥; 尚平; 杨俊龙; 赖震

    2015-01-01

    目的 观察抗生素灌洗疗法联合高压氧治疗骨髓炎的临床治疗效果. 方法 将62例慢性骨髓炎患者随机分为研究组和对照组,每组31例. 所有患者均反复清创,大量抗生素生理盐水灌注冲洗引流,同时进行长期抗生素控制. 研究组在此基础上应用高压氧治疗. 比较两组患者的治愈率、复发率、细菌检出率、抗生素应用时间、愈合时间、住院时间和炎症因子水平. 结果 研究组治愈率显著高于对照组(p0.05),治疗后研究组患者的IL-6和TNF-α水平均显著低于对照组( p0.05).After treatment, both of the IL-6 and TNF-αin in the experiment group were significantly less than those of the control group (p<0.01). Conclusion Antibiotic irrigation combined with hyperbaric oxygen therapy has a great clinical efficacy on osteomyeli-tis, and therefore is worthy of clinical application.

  5. 替勃龙联合高压氧治疗更年期综合征的临床效果%Clinical efficacy of tibolone combined with hyperbaric oxygen in treatment of menopausal syndrome

    Institute of Scientific and Technical Information of China (English)

    陈隽

    2012-01-01

    Objective: To explore the clinical efficacy of tibolone combined with hyperbaric oxygen in treatment of menopausal syndrome. Methods: Ninety -six patients with menopausal syndrome were randomly divided into experimental group (SO cases) and control group (46 cases), the patients in experimental group were treated with tibolone combined with hyperbaric oxygen, while the patients in control group were treated with tibolone, the courses of treatment in the two groups were 30 days, Kupperman scale, self - rating anxiety scale (SAS), and self-rating depression scale (SDS) were conducted in the two groups before and after treatment, radioimmunoassay was used lo detect serum levels of estradiol, follicle - stimulating hormone ( FSH) , and luteinizing hormone ( LH) . Results: Kupperman score, SAS score, and SDS score in the two groups after treatment were significantly lower than those before treatment (P <0.05) ; Kupperman score, SAS score, and SDS score after treatment in experimental group were significantly lower than those in control group (P < 0.05 ) . The serum levels of estradiol in the two groups after treatment were significantly higher than those before treatment, while the serum levels of FSH and LH in the two groups after treatment were significantly lower than those before treatment (P < 0.05) . The degree of increase of serum estradiol and the degrees of decrease of serum FSH and LH in experimental group were significantly higher than those in control group (P < 0.05) . Conclusion: Tibolone combined with hyperbaric oxygen used for the patients with menopausal syndrome can improve the serum levels of relevant hormones and relieve the symptoms of menopausal syndrome effectively, especially anxiety and depression, which become to be a new and effective method for treatment of menopausal syndrome, and it has good social benefits.%目的:探讨替勃龙联合高压氧治疗更年期综合征的临床效果.方法:将96例更年期综合

  6. Efecto de la mezcla ozono/oxigeno combinado con levofloxacina en un modelo de sepsis peritoneal en rata (Efect of ozone/oxygen mixture combined with levofloxacin in a model of peritoneal sepsis induced in rats

    Directory of Open Access Journals (Sweden)

    DMV. Zullyt Zamora Rodríguez

    2007-09-01

    Full Text Available ResumenEl objetivo de este trabajo fue evaluar el efecto de la mezcla ozono/oxígeno combinado con antibiótico y aplicado terapéuticamente en un modelo de sepsis peritoneal en rata. El estudio fue realizado en ratas Wistar macho (200-250 g, los cuales fueron divididos aleatoriamente en cinco grupos: 1. inducción de la infección peritoneal, sin tratamiento alguno; 2. infectados y tratados con levofloxacina (25mg/kg; 3. infectados y tratados con la mezcla ozono/oxigeno por vía intraperitoneal, a la dosis de 1 mg/kg de peso; 4 y 5. infectados y tratados con Levofloxacina (25 mg/kg más la mezcla ozono/oxigeno i.p a 0,4 y 1 mg/kg, respectivamente. Se determinó el porciento de mortalidad de los animales mediante la observación diaria y también se registró el peso de los animales. Los resultados mostraron que los grupos de animales que recibieron tratamientos combinados de antibiótico y la mezcla ozono/oxígeno tuvieron un elevado porciento de sobrevivencia, siendo del 77 hasta el 100 % a las 120 h y entre el 66 y el 77 % a las 240 h. Sin embargo, en el grupo tratado con antibiótico fue de un 77% a las 120 h, pero ya a las 240 h el por ciento de sobrevivencia fue del 33 %. Este estudio demostró la efectividad de la combinación de la mezcla ozono/oxígeno con un antibiótico de última generación. Sin embargo, la aplicación sola de ozono de forma terapéutica, por vía intraperitoneal, en este modelo de sepsis no fue efectivo por lo cual se requiere evaluar otras dosis y vías de administración del ozono. AbstractThe aim of this research was to evaluate the effect of ozone / oxygen mixture (OOM combined with an antibiotic and applied therapeutically in a model of peritoneal sepsis induced by rat faecal material. The study was performed in male Wistar rats weighing 200-250 g. The animals were divided in five groups. The first one was the infected control with faecal material alone. The second was also infected and treated with

  7. Hyperbaric oxygen in chronic traumatic brain injury: oxygen, pressure, and gene therapy.

    Science.gov (United States)

    Harch, Paul G

    2015-01-01

    Hyperbaric oxygen therapy is a treatment for wounds in any location and of any duration that has been misunderstood for 353 years. Since 2008 it has been applied to the persistent post-concussion syndrome of mild traumatic brain injury by civilian and later military researchers with apparent conflicting results. The civilian studies are positive and the military-funded studies are a mixture of misinterpreted positive data, indeterminate data, and negative data. This has confused the medical, academic, and lay communities. The source of the confusion is a fundamental misunderstanding of the definition, principles, and mechanisms of action of hyperbaric oxygen therapy. This article argues that the traditional definition of hyperbaric oxygen therapy is arbitrary. The article establishes a scientific definition of hyperbaric oxygen therapy as a wound-healing therapy of combined increased atmospheric pressure and pressure of oxygen over ambient atmospheric pressure and pressure of oxygen whose main mechanisms of action are gene-mediated. Hyperbaric oxygen therapy exerts its wound-healing effects by expression and suppression of thousands of genes. The dominant gene actions are upregulation of trophic and anti-inflammatory genes and down-regulation of pro-inflammatory and apoptotic genes. The combination of genes affected depends on the different combinations of total pressure and pressure of oxygen. Understanding that hyperbaric oxygen therapy is a pressure and oxygen dose-dependent gene therapy allows for reconciliation of the conflicting TBI study results as outcomes of different doses of pressure and oxygen.

  8. Artificial oxygen transport protein

    Science.gov (United States)

    Dutton, P. Leslie

    2014-09-30

    This invention provides heme-containing peptides capable of binding molecular oxygen at room temperature. These compounds may be useful in the absorption of molecular oxygen from molecular oxygen-containing atmospheres. Also included in the invention are methods for treating an oxygen transport deficiency in a mammal.

  9. Oxygen sensing and signaling.

    Science.gov (United States)

    van Dongen, Joost T; Licausi, Francesco

    2015-01-01

    Oxygen is an indispensable substrate for many biochemical reactions in plants, including energy metabolism (respiration). Despite its importance, plants lack an active transport mechanism to distribute oxygen to all cells. Therefore, steep oxygen gradients occur within most plant tissues, which can be exacerbated by environmental perturbations that further reduce oxygen availability. Plants possess various responses to cope with spatial and temporal variations in oxygen availability, many of which involve metabolic adaptations to deal with energy crises induced by low oxygen. Responses are induced gradually when oxygen concentrations decrease and are rapidly reversed upon reoxygenation. A direct effect of the oxygen level can be observed in the stability, and thus activity, of various transcription factors that control the expression of hypoxia-induced genes. Additional signaling pathways are activated by the impact of oxygen deficiency on mitochondrial and chloroplast functioning. Here, we describe the molecular components of the oxygen-sensing pathway.

  10. Longitudial observation of dynamic changes in cortical function and white matter fibrous structure of patients with visual pathway lesions by blood oxygenation level dependent-functional magnetic resonance imaging combined with diffusion tensor imaging

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Functional magnetic resonance imaging (fMRI) is initially used for visual cortex location.However, the application of fMRI in investigating the development of visual pathway lesions needs to be further observed.OBJECTIVE: This study is to longitudially observe the dynamic changes in cortical function and white matter fibrous structure of patients with visual pathway lesions by blood oxygenation level dependent-functional magnetic resonance imaging (BOLD-fMRI) combined with diffusion tensor imaging (DTI), and to analyze the characteristics of brain function and structural recombination at convalescent period of lesions.DESIGN: Randomized controlled observation.SETTING: Department of Radiology, the General Hospital of Nanjing Military Area Command of Chinese PLA.PARTICIPANTS: Eight patients with unilateral or bilateral visual disorder caused by visual pathway lesions,who admitted to Department of Radiology, the General Hospital of Nanjing Military Area Command of Chinese PLA from January to September 2006 were involved, and served as experimental subjects. The patients, 6 males and 2 females, were aged 16 - 67 years. They had visual disorder confirmed by clinical examination, i.e. visual pathway lesion, which was further diagnosed by MR or CT. Another 12 subjects generally matching to those patients of experimental group in gender, age and sight, who received health examination in synchronization were involved and served as controls. The subjects had no history of eye diseases. Their binocular visual acuity (or corrected visual acuity) was over 1.0. Both routine examination of ophthalmology and examination of fundus were normal. Informed consents of detected items were obtained from all the subjects.METHODS: Signa Excite HD 1.5T magnetic resonance imaging system with 16 passages (GE Company,USA) and coil with 8 passages were used; brain functional stimulus apparatus (SAV-8800. Meide Company) was used for showing experimental mission. At the early stage

  11. Oxygen-enhanced combustion

    CERN Document Server

    Baukal, Charles E

    2013-01-01

    Combustion technology has traditionally been dominated by air/fuel combustion. However, two developments have increased the significance of oxygen-enhanced combustion-new technologies that produce oxygen less expensively and the increased importance of environmental regulations. Advantages of oxygen-enhanced combustion include less pollutant emissions as well as increased energy efficiency and productivity. Oxygen-Enhanced Combustion, Second Edition compiles information about using oxygen to enhance industrial heating and melting processes. It integrates fundamental principles, applications, a

  12. Analysis of curative effect of Ginaton combined with hyperbaric oxygen in the treatment of sudden deafness%金纳多联合高压氧治疗突发性聋的疗效分析

    Institute of Scientific and Technical Information of China (English)

    张姝; 李玲香

    2014-01-01

    Objective To analyze the curative effect of EGb761 combined with Hyperbaric Oxygen therapy on Sudden hearing loss and to explore relationship between some correlative influencing factors and the therapeutic effect. Methods summarize and analyze the clinical data of 150 Sudden hearing loss patients from Jan 2010 to Dec 2011 in a retrospective way and to evaluate the efficacy. Results 1. In the comparison group, the female、the middle-aged people、the mental work-ers、little movement persons、general tension persons、single ear unwell’person occupies the highest proportion.2. among the 150 patients, 49 cases is cured, 30 cases is markedly effective,27 cases ineffective and53 cases is failed, and the total effec-tive rate was 62.72%.3. Taking all factor into consideration in this study, puretone threshold , Accompanied by dizziness, the length of time between attack and reception of treatment in effect of sudden deafness are of statistical meaning(P0.05). Conclusion 1. Middle-aged people and younger one have higher risks of sudden deafness. The mental worker is the main group. The main factors are high pressure, tired and lower quality of sleep. 2. Patients with EGb761 combined with Hyperbaric Oxygen treatment on the hearing type of low-frequency steep drop will have a better curative effect. Patients with high-frequency hearing loss or complete deafness hearing curve type of ill have a bad curative effect. 3. The main factor influence the curative effect of sudden hearing loss are hearing type graphs and the length of time between attack and reception of treatment.%目的:分析金纳多联合高压氧治疗突发性聋的疗效,并探讨突发性聋的相关发病因素与疗效的关系。方法回顾性总结分析2010年1月至2011年12月在我院诊断并治疗的150例突发性聋患者的一般临床资料并进行疗效评估。结果1、150例患者发病构成比调查中:女性、中年人、脑力劳动者、很少运动者、一般紧张

  13. HYPERBARIC OXYGENATION AND AEROBIC PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Irvine D. Prather

    2004-03-01

    Full Text Available The continuing desire to improve performance, particularly at the national and international levels, has led to the use of ergogenic aids. Ergogenic aids are defined as 'a procedure or agent that provides the athlete with a competitive edge beyond that obtained via normal training methods'. Random drug testing has been implemented in an effort to minimize an athlete's ability to gain an unfair advantage. However, other means of improving performance have been tried. Blood doping has been used to enhance endurance performance by improving oxygen delivery to working muscles. As oxygen is carried in combination with the hemoglobin, it seems logical that increasing the number of red blood cells (RBC's in the body would increase the oxygen carrying capacity to the tissues and result in improved performance. The first experiments of removing and then reinfusing blood showed a significant improvement in performance time

  14. Oxygen Transport Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay

    2008-08-30

    The focus of this research was to develop new membrane materials by synthesizing different compounds and determining their defect structures, crystallographic structures and electrical properties. In addition to measuring electrical conductivity, oxygen vacancy concentration was also evaluated using thermogravimetry, Neutron diffraction and Moessbauer Spectroscopy. The reducing conditions (CO{sub 2}/CO/H{sub 2} gas mixtures with steam) as encountered in a reactor environment can be expected to have significant influence on the mechanical properties of the oxides membranes. Various La based materials with and without Ti were selected as candidate membrane materials for OTM. The maximum electrical conductivity of LSF in air as a function of temperature was achieved at < 600 C and depends on the concentration of Sr (acceptor dopant). Oxygen occupancy in LSF was estimated using Neutron diffractometry and Moessbauer Spectroscopy by measuring magnetic moment changes depending on the Fe{sup 3+} and Fe{sup 4+} ratio. After extensive studies of candidate materials, lanthanum ferrites (LSF and LSFT) were selected as the favored materials for the oxygen transport membrane (OTM). LSF is a very good material for an OTM because of its high electronic and oxygen ionic conductivity if long term stability and mechanical strength are improved. LSFT not only exhibits p-type behavior in the high oxygen activity regime, but also has n-type conduction in reducing atmospheres. Higher concentrations of oxygen vacancies in the low oxygen activity regime may improve the performance of LSFT as an OTM. The hole concentration is related to the difference in the acceptor and donor concentration by the relation p = [Sr'{sub La}]-[Ti{sm_bullet}{sub Fe}]. The chemical formulation predicts that the hole concentration is, p = 0.8-0.45 or 0.35. Experimental measurements indicated that p is about {approx} 0.35. The activation energy of conduction is 0.2 eV which implies that LSCF conducts via the

  15. The Effect of Oxiracetam Combined with Hyperbaric Oxygen for Treating Memory and Intelligence in Patients with Severe Craniocerebral Trauma%高压氧联合奥拉西坦对重型颅脑外伤患者记忆与智能的影响

    Institute of Scientific and Technical Information of China (English)

    熊浩峰; 程强; 彭礼波; 霍建宏; 何有虎

    2013-01-01

    目的 观察高压氧联合奥拉西坦治疗重型颅脑外伤患者记忆与智能障碍的临床疗效.方法 将60例重型颅脑外伤患者随机分为4组,对照组、高压氧治疗组、奥拉西坦治疗组和高压氧联合奥拉西坦治疗组.运用简易精神状态量表(MMSE)和巴氏指数(BI)测定治疗前和治疗60 d后4组患者的评分值.结果 高压氧联合奥拉西坦组MMSE及BI评分增加值明显高于奥拉西坦组和高压氧组(P<0.05).结论 高压氧联合奥拉西坦治疗重型颅脑外伤恢复期患者的记忆与智能障碍有显著临床疗效.%Objective To observe the curative effect of oxiracetam combined with hyperbaric oxygen tor treating the impediment ot memory and intelligence in the patients with severe craniocerebral trauma.Methods Sixty cases of severe craniocerebral trauma were randomly assigned to 4 groups:control group,hyperbaric oxygen treatment group,oxiracetam treatment group and oxiracetam combined with hyperbaric oxygen treatment group.The scores of the Mini-Mental State Examination(MMSE) and the Barthel index(BI) were determined before treatment and on 60 d after treatment.Methods The increment value of MMSE and BI of the oxiracetam combined with hyperbaric oxygen treatment group was significantly higher than that in the oxiracetam treatment group and the hyperbaric oxygen treatment group (P < 0.05).Conclusion Hyperbaric oxygen combined with oxiracetam has significantly clinical effect for treating the impediment of memory and intelligence in the convalescent patients with severe craniocerebral trauma.

  16. Oxygen Chemistry in Titan's Atmosphere

    Science.gov (United States)

    Wilson, E. H.; Atreya, S. K.

    2002-09-01

    Oxygen chemistry in the atmosphere of Titan is controlled by the presence of CO and a likely influx of extraplanetary oxygen. The presence of water vapor, corroborated by the Infrared Space Observatory (ISO) stratospheric detection [1], combined with CO induces the formation of CO2, which has also been observed [2]. However, the high CO/H2O ratio in Titan's atmosphere causes the propagation of oxygen chemistry to follow a different path than what is predicted for the Jovian planets. Specifically, the efficient CO recycling mechanisms serve to inhibit significant formation of larger oxygen compounds such as CH3OH (methanol) and CH2CO (ketene). The results of a 1-D photochemical model are presented in the context of identifying possible oxygen compounds that might be detected by the Cassini/Huygens mission which will arrive at Titan in 2004. This work was supported by the NASA Planetary Atmospheres Program and by the GCMS Project of the Cassini/Huygens mission. [1] A. Coustenis et al., Astron. Astrophys., 336, L85-L89, 1998. [2] A. Coustenis et al., Icarus, 80, 54-76, 1989.

  17. 稳定期COPD患者长期家庭氧疗及联合应用茶碱缓释片与噻托溴铵的疗效观察%Effect appraise of long term domiciliary oxygen therapy(LTDOT) combined theophylline sustained-release tablets and tiotropium bromide in the treatment of stable

    Institute of Scientific and Technical Information of China (English)

    曹雪如

    2014-01-01

    Objective To evaluate the effects of LTDOT combined with theophylline sustained-release tablets and tiotropium bromide in the treatment of stable COPD. Methods 82 Patients were randomly divided into LTDOT group and combination group, given oxygen supplement, theophylline combined with tiotropium bromide. Results After 6 months therapy, lung function, six-minutes walking distance, the scores of life quality and blood gas analysis of combination group were improved significant(P0.05)。结论稳定期COPD患者长期家庭氧疗联合茶碱缓释片与噻托溴铵能明显改善患者肺功能,提高运动耐量和生活质量,且无明显副作用,值得临床推广应用。

  18. Application of hearing test combination in sensorineural deafness with hyperbaric oxygen treatment%听力测试组合在高压氧治疗感音神经性耳聋中的应用

    Institute of Scientific and Technical Information of China (English)

    王秋莎; 田树昌; 孙爱华; 高春锦; 王培嵩; 俞海安; 钱文华; 孙学军

    2008-01-01

    Objective To study the relationship between the cochlear hair cell and sensorineural deafness,so as to explore hearing test method for early intervention and discovery.Methods Two hundred and fifty-three patients suffered from sensorineural deafness with hyperbaric oxygen(HBO)treatment were randomly seleceted,curative effect before and after HBO treantment were recorded and compared,respectively.Examinations of acoustic brainstem evoked respone(ABR)and distortion product otoacoustic emission(DPOAE)were conducted for the evaluation of hearing test result.Results It Was revealed that total effective rate of mild hearing loss after two courses of HBO treatment was significantly higher than that of moderate deafness.There Was significant difference in the incidence of abnormal ratio of ABR between pretherapy and aftertherapy of HBO(P<0.05).DPOAE amplitude obviously decreased after one and two courses of HBO treatment.At 1.4-6.0 kHz frequency before and one course of HBO treatment.there was a slight upward.Conclusions HBO may have therapeutic efficacy on sensorineural deafness by revive the activity of cochlear hair apoptosis cell.DPOAE is more sensitive and prospective than ABR.The combination of ABR and DPOAE Can be used to judge the degree of hearing impairment and recovery.%目的 寻找感音神经性耳聋的发病与耳蜗毛细胞损伤的联系,探讨早期发现、早期干预本病的听力测试方法.方法 从进行高压氧(HBO)治疗的感音神经性耳聋患者中随机选出253人,对HBO治疗前、治疗1、2个疗程后的治疗效果进行比较;行听性脑干反应(ABR)、畸变产物耳声发射(DPOAE)听力测试,并对结果进行比较.结果 HBO治疗2个疗程后轻度耳聋治愈率与总有效率显著高于中度耳聋;HBO治疗1、2个疗程后与治疗前、治疗1个疗程后与2个疗程后ABR异常的发生率相比,差异有统计学意义(P<0.05).HBO治疗前与治疗2个疗程后比较,治疗1个疗程后与治疗2个疗程

  19. Oxygen transport membrane

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof.......The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof....

  20. Hyperbaric oxygen therapy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002375.htm Hyperbaric oxygen therapy To use the sharing features on this page, please enable JavaScript. Hyperbaric oxygen therapy uses a special pressure chamber to increase ...

  1. Home Oxygen Therapy

    Science.gov (United States)

    ... Teenagers Living With Lung Disease Articles written by Respiratory Experts Home Oxygen Therapy More and more people are using oxygen therapy ... April 12, 2012 Revised: © 2017 American Association for Respiratory Care

  2. Biogeochemistry: Oxygen burrowed away

    NARCIS (Netherlands)

    Meysman, F.J.R.

    2014-01-01

    Multicellular animals probably evolved at the seafloor after a rise in oceanic oxygen levels. Biogeochemical model simulations suggest that as these animals started to rework the seafloor, they triggered a negative feedback that reduced global oxygen.

  3. Oxygen evolution reaction catalysis

    Science.gov (United States)

    Haber, Joel A.; Jin, Jian; Xiang, Chengxiang; Gregoire, John M.; Jones, Ryan J.; Guevarra, Dan W.; Shinde, Aniketa A.

    2016-09-06

    An Oxygen Evolution Reaction (OER) catalyst includes a metal oxide that includes oxygen, cerium, and one or more second metals. In some instances, the cerium is 10 to 80 molar % of the metals in the metal oxide and/or the catalyst includes two or more second metals. The OER catalyst can be included in or on an electrode. The electrode can be arranged in an oxygen evolution system such that the Oxygen Evolution Reaction occurs at the electrode.

  4. Relationship Between Cerebral Oxygenation and Hemodynamic and Oxygen Transport Parameters in Surgery for Acquired Heart Diseases

    Directory of Open Access Journals (Sweden)

    A. I. Lenkin

    2012-01-01

    Full Text Available Objective: to evaluate the relationship between cerebral oxygenation and hemodynamic and oxygen transport parameters in surgical correction of concomitant acquired heart diseases. Subjects and methods. Informed consent was received from 40 patients who required surgery because of concomitant (two or more acquired heart defects. During procedure, perioperative monitoring of oxygen transport and cerebral oxygenation was performed with the aid of PiCCO2 monitor (Pulsion Medical Systems, Germany and a Fore-Sight cerebral oximeter (CASMED, USA. Anesthesia was maintained with propofol and fen-tanyl, by monitoring the depth of anesthesia. Early postoperative intensive therapy was based on the protocol for early targeted correction of hemodynamic disorders. Oxygen transport and cerebral oxygenation parameters were estimated intraopera-tively and within 24 postoperative hours. A statistical analysis including evaluation of Spearman correlations was performed with the aid of SPSS 15.0. Results. During perfusion, there was a relationship between cerebral oximetry values and hemat-ocrit levels, and oxygen partial pressure in the venous blood. Furthermore, a negative correlation between cerebral oximetry values and blood lactate levels was found 30 minutes after initiation of extracorporeal circulation (EC. During the study, there was a positive correlation between cerebral oxygenation and values of cardiac index, central venous saturation, and oxygen delivery index. There was a negative relationship between cerebral oxygenation and extravascular lung water at the beginning of surgery and a correlation between cerebral oximetry values and oxygenation index by the end of the first 24 postoperative hours. Conclusion. The cerebral oxygenation values correlate -with the main determinants of oxygen transport during EC and after cardiac surgical procedures. Cerebral oximetry may be used in early targeted therapy for the surgical correction of acquired combined

  5. High Selectivity Oxygen Delignification

    Energy Technology Data Exchange (ETDEWEB)

    Arthur J. Ragauskas

    2005-09-30

    yield and 4 cP in viscosity in comparison to high AA pulp for the oxygen delignification. This difference is also seen for high-kappa SW kraft pulps with an average improvement of {approx}3% in yield and 3 cP in viscosity for low AA high kappa number 50 pulp. Low AA hardwood kappa number 20 pulp had an average improvement of {approx}4% in yield and 6-12 cP in viscosity as compared to high AA pulp. Lower kraft cooking temperature (160 vs. 170 C) in combination with the medium AA provides a practical approach for integrating high kappa pulping of hardwoods (i.e., low rejects) with an advanced extended oxygen delignification stage. ECF pulp bleaching of low and high kappa kraft SW and HW pulps exhibit comparable optical and physical strength properties when bleached D(EPO)D.

  6. Saturn's Stratospheric Oxygen Compounds

    Science.gov (United States)

    Romani, Paul N.; Delgado Díaz, Héctor E.; Bjoraker, Gordon; Hesman, Brigette; Achterberg, Richard

    2016-10-01

    There are three known oxygenated species present in Saturn's upper atmosphere: H2O, CO and CO2. The ultimate source of the water must be external to Saturn as Saturn's cold tropopause effectively prevents any internal water from reaching the upper atmosphere. The carbon monoxide and dioxide source(s) could be internal, external, produced by the photochemical interaction of water with Saturn's stratospheric hydrocarbons or some combination of all of these. At this point it is not clear what the external source(s) are.Cassini's Composite InfraRed Spectrometer (CIRS) has detected emission lines of H2O and CO2 (Hesman et al., DPS 2015, 311.16 & Abbas et al. 2013, Ap. J. doi:10.1088/0004-637X/776/2/73) on Saturn. CIRS also retrieves the temperature of the stratosphere using CH4 lines at 7.7 microns. Using CIRS retrieved temperatures, the mole fraction of H2O at the 0.5-5 mbar level can be retrieved and the CO2 mole fraction at ~1-10 mbar. Coupled with ground based observations of CO (Cavalié et al., 2010, A&A, DOI: 10.1051/0004-6361/200912909) these observations provide a complete oxygen compound data set to test photochemical models.Preliminary results will be presented with an emphasis on upper limit analysis to determine the percentage of stratospheric CO and CO2 that can be produced photochemically from CIRS observational constraints on the H2O profile.

  7. 42 CFR 414.226 - Oxygen and oxygen equipment.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Oxygen and oxygen equipment. 414.226 Section 414... Equipment and Prosthetic and Orthotic Devices § 414.226 Oxygen and oxygen equipment. (a) Payment rules—(1) Oxygen equipment. Payment for rental of oxygen equipment is made based on a monthly fee schedule...

  8. Yttrium doped BSCF membranes for oxygen separation

    DEFF Research Database (Denmark)

    Haworth, P.; Smart, S.; Glasscock, Julie;

    2011-01-01

    (x = 0.2) for iron resulted in a non-cubic crystal structure that did not exhibit oxygen permeation. The yttrium partial substitution in BSCFY discs (1.2 mm thick) delivered best results for x = 0.025, as oxygen fluxes reached 2.05 ml cm−2 min−1 at 900 °C, an increase of 160% as compared to a blank...... BSCF (x = 0) membrane. This was attributed to the combined effect of the formation of a greater number of oxygen vacancies, together with improved ion mobility, associated with the beneficial yttrium substitution into the BSCF perovskite structure which stemmed from the crystal lattice expansion....

  9. How plasma induced oxidation, oxygenation, and de-oxygenation influences viability of skin cells

    Science.gov (United States)

    Oh, Jun-Seok; Strudwick, Xanthe; Short, Robert D.; Ogawa, Kotaro; Hatta, Akimitsu; Furuta, Hiroshi; Gaur, Nishtha; Hong, Sung-Ha; Cowin, Allison J.; Fukuhara, Hideo; Inoue, Keiji; Ito, Masafumi; Charles, Christine; Boswell, Roderick W.; Bradley, James W.; Graves, David B.; Szili, Endre J.

    2016-11-01

    The effect of oxidation, oxygenation, and de-oxygenation arising from He gas jet and He plasma jet treatments on the viability of skin cells cultured in vitro has been investigated. He gas jet treatment de-oxygenated cell culture medium in a process referred to as "sparging." He plasma jet treatments oxidized, as well as oxygenated or de-oxygenated cell culture medium depending on the dissolved oxygen concentration at the time of treatment. He gas and plasma jets were shown to have beneficial or deleterious effects on skin cells depending on the concentration of dissolved oxygen and other oxidative molecules at the time of treatment. Different combinations of treatments with He gas and plasma jets can be used to modulate the concentrations of dissolved oxygen and other oxidative molecules to influence cell viability. This study highlights the importance of a priori knowledge of the concentration of dissolved oxygen at the time of plasma jet treatment, given the potential for significant impact on the biological or medical outcome. Monitoring and controlling the dynamic changes in dissolved oxygen is essential in order to develop effective strategies for the use of cold atmospheric plasma jets in biology and medicine.

  10. Combined Treatment With Peroxisome Proliferator-Activated Receptor (PPAR) Gamma Ligands and Gamma Radiation Induces Apoptosis by PPARγ-Independent Up-Regulation of Reactive Oxygen Species-Induced Deoxyribonucleic Acid Damage Signals in Non-Small Cell Lung Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Jong; Im, Chang-Nim; Park, Seon Hwa [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Moon, Eun-Yi [Department of Bioscience and Biotechnology, Sejong University, Seoul (Korea, Republic of); Hong, Sung Hee, E-mail: gobrian@kcch.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2013-04-01

    Purpose: To investigate possible radiosensitizing activities of the well-known peroxisome proliferator-activated receptor (PPAR)γ ligand ciglitazone and novel PPARγ ligands CAY10415 and CAY10506 in non-small cell lung cancer (NSCLC) cells. Methods and Materials: Radiosensitivity was assessed using a clonogenic cell survival assay. To investigate the mechanism underlying PPARγ ligand-induced radiosensitization, the subdiploid cellular DNA fraction was analyzed by flow cytometry. Activation of the caspase pathway by combined PPARγ ligands and γ-radiation treatment was detected by immunoblot analysis. Reactive oxygen species (ROS) were measured using 2,7-dichlorodihydrofluorescein diacetate and flow cytometry. Results: The 3 PPARγ ligands induced cell death and ROS generation in a PPARγ-independent manner, enhanced γ-radiation–induced apoptosis and caspase-3–mediated poly (ADP-ribose) polymerase (PARP) cleavage in vitro. The combined PPARγ ligand/γ-radiation treatment triggered caspase-8 activation, and this initiator caspase played an important role in the combination-induced apoptosis. Peroxisome proliferator-activated receptor-γ ligands may enhance the γ-radiation-induced DNA damage response, possibly by increasing γ-H2AX expression. Moreover, the combination treatment significantly increased ROS generation, and the ROS scavenger N-acetylcysteine inhibited the combined treatment-induced ROS generation and apoptotic cell death. Conclusions: Taken together, these results indicated that the combined treatment of PPARγ ligands and γ-radiation synergistically induced DNA damage and apoptosis, which was regulated by ROS.

  11. Modeling Oxygen Transport in the Human Placenta

    Science.gov (United States)

    Serov, Alexander; Filoche, Marcel; Salafia, Carolyn; Grebenkov, Denis

    Efficient functioning of the human placenta is crucial for the favorable pregnancy outcome. We construct a 3D model of oxygen transport in the placenta based on its histological cross-sections. The model accounts for both diffusion and convention of oxygen in the intervillous space and allows one to estimate oxygen uptake of a placentone. We demonstrate the existence of an optimal villi density maximizing the uptake and explain it as a trade-off between the incoming oxygen flow and the absorbing villous surface. Calculations performed for arbitrary shapes of fetal villi show that only two geometrical characteristics - villi density and the effective villi radius - are required to predict fetal oxygen uptake. Two combinations of physiological parameters that determine oxygen uptake are also identified: maximal oxygen inflow of a placentone and the Damköhler number. An automatic image analysis method is developed and applied to 22 healthy placental cross-sections demonstrating that villi density of a healthy human placenta lies within 10% of the optimal value, while overall geometry efficiency is rather low (around 30-40%). In a perspective, the model can constitute the base of a reliable tool of post partum oxygen exchange efficiency assessment in the human placenta. Also affiliated with Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA 90095, USA.

  12. Composite oxygen ion transport element

    Science.gov (United States)

    Chen, Jack C.; Besecker, Charles J.; Chen, Hancun; Robinson, Earil T.

    2007-06-12

    A composite oxygen ion transport element that has a layered structure formed by a dense layer to transport oxygen ions and electrons and a porous support layer to provide mechanical support. The dense layer can be formed of a mixture of a mixed conductor, an ionic conductor, and a metal. The porous support layer can be fabricated from an oxide dispersion strengthened metal, a metal-reinforced intermetallic alloy, a boron-doped Mo.sub.5Si.sub.3-based intermetallic alloy or combinations thereof. The support layer can be provided with a network of non-interconnected pores and each of said pores communicates between opposite surfaces of said support layer. Such a support layer can be advantageously employed to reduce diffusion resistance in any type of element, including those using a different material makeup than that outlined above.

  13. Ambient oxygen promotes tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Ho Joong Sung

    Full Text Available Oxygen serves as an essential factor for oxidative stress, and it has been shown to be a mutagen in bacteria. While it is well established that ambient oxygen can also cause genomic instability in cultured mammalian cells, its effect on de novo tumorigenesis at the organismal level is unclear. Herein, by decreasing ambient oxygen exposure, we report a ∼50% increase in the median tumor-free survival time of p53-/- mice. In the thymus, reducing oxygen exposure decreased the levels of oxidative DNA damage and RAG recombinase, both of which are known to promote lymphomagenesis in p53-/- mice. Oxygen is further shown to be associated with genomic instability in two additional cancer models involving the APC tumor suppressor gene and chemical carcinogenesis. Together, these observations represent the first report directly testing the effect of ambient oxygen on de novo tumorigenesis and provide important physiologic evidence demonstrating its critical role in increasing genomic instability in vivo.

  14. Integrated turbomachine oxygen plant

    Science.gov (United States)

    Anand, Ashok Kumar; DePuy, Richard Anthony; Muthaiah, Veerappan

    2014-06-17

    An integrated turbomachine oxygen plant includes a turbomachine and an air separation unit. One or more compressor pathways flow compressed air from a compressor through one or more of a combustor and a turbine expander to cool the combustor and/or the turbine expander. An air separation unit is operably connected to the one or more compressor pathways and is configured to separate the compressed air into oxygen and oxygen-depleted air. A method of air separation in an integrated turbomachine oxygen plant includes compressing a flow of air in a compressor of a turbomachine. The compressed flow of air is flowed through one or more of a combustor and a turbine expander of the turbomachine to cool the combustor and/or the turbine expander. The compressed flow of air is directed to an air separation unit and is separated into oxygen and oxygen-depleted air.

  15. 高压氧联合药物治疗脑胶质瘤模型鼠效果研究%Study on the therapeutic effects of hyperbaric oxygen combined with drugs on glioma in model mice

    Institute of Scientific and Technical Information of China (English)

    陆朝晖; 刘兵; 马笑宇; 戴纯刚; 贾敬云; 谢涛; 芮琴; 王爱东; 兰青

    2015-01-01

    Objective To investigate the therapeutic effects of the chemotherapeutic drug ACNU combined with hyperbaric oxygen (HBO) in the treatment of transplantation tumor of glioma stem/progenitor cells SU3.Methods The SU3 cells were inoculated subcutaneously into general NC nude mice which were kept in an independent ventilated cages (IVC).Following the development of the tumor,the tumor-bearing mice were sacrificed,and tumor tissues were harvested,then,inoculated subcutaneously into transgenic green fluorescence protein (GFP) nude mice.On the third day,the animals were randomly divided into 4 groups:the HBO group (n =7),the ACNU + HBO group (n =7),the ACNU group (n =7) and the control group (n =12).The first 2 groups were placed in the HBO-IVC without specific pathogens and treated with HBO,1 session a day for a duration of 100 minutes.The animals in the second and third groups were administered with ACNU abdominally at a dosage of 30 mg/kg,once a week for a duration of 3 weeks.The tumor volume was measured with the vernier caliper and the body mass of tumor-bearing mice was weighed with the balance weight,once every 3 days.At the end of the experiment,some tissues were collected to perform RT-PCR detection,the remaining tissues were used for pathological sections.Results As compared with those of the control group,changes in the transplantation tumor mass of various groups were as follows:The tumor mass for the ACNU + HBO group was (2 252.86 ± 1 062.54) mg (P =0.006);the tumor mass for the ACNU group was (1 914.28 ±744.55) mg (P=0.002);that for the HBO group was (4 680.00 ±2 538.40) mg(P =0.925);and that for the control group was (4 760.83 ± 1 989.18) mg.Histopathological examination indicated that necrotic hemorrhage foci in tumor tissues could be frequently observed in the control group,and numerous neoformative vessels around the hemorrhagic site could also be found.Proliferation of vascular endothelial cells was quite active under microscopy

  16. Solid state oxygen sensor

    Science.gov (United States)

    Garzon, F.H.; Brosha, E.L.

    1997-12-09

    A potentiometric oxygen sensor is formed having a logarithmic response to a differential oxygen concentration while operating as a Nernstian-type sensor. Very thin films of mixed conducting oxide materials form electrode services while permitting diffusional oxygen access to the interface between the zirconia electrolyte and the electrode. Diffusion of oxygen through the mixed oxide is not rate-limiting. Metal electrodes are not used so that morphological changes in the electrode structure do not occur during extended operation at elevated temperatures. 6 figs.

  17. Measuring tissue oxygenation

    Science.gov (United States)

    Soyemi, Olusola O. (Inventor); Soller, Babs R. (Inventor); Yang, Ye (Inventor)

    2009-01-01

    Methods and systems for calculating tissue oxygenation, e.g., oxygen saturation, in a target tissue are disclosed. In some embodiments, the methods include: (a) directing incident radiation to a target tissue and determining reflectance spectra of the target tissue by measuring intensities of reflected radiation from the target tissue at a plurality of radiation wavelengths; (b) correcting the measured intensities of the reflectance spectra to reduce contributions thereto from skin and fat layers through which the incident radiation propagates; (c) determining oxygen saturation in the target tissue based on the corrected reflectance spectra; and (d) outputting the determined value of oxygen saturation.

  18. 经皮穴位电刺激配合全麻行异氟醚控制性降压对组织氧代谢的影响%Effects of Combined Transdermal Acupoint Electric Stimulation and Isoflurane Anesthesia on Isoflurane-Induced Hypotension and Tissue Oxygen Metabolism in Patients Undergoing Craniotomy

    Institute of Scientific and Technical Information of China (English)

    王均炉; 谢文霞; 张琦

    2001-01-01

    Objective: To observe the effects of combined transdermalacupoint electric stimulation and isoflurane anesthesia on isoflurane-induced hypotension and tissue oxygen metabolism in patients undergoing craniotomy. Methods: Forty-two patients with brain tumor of ASA physical status Ⅰ or Ⅱ and scheduled for elective surgery were randomly divided into two groups. The craniotomy was undergoing in Group A with isoflurane anesthesia, while in Group B, with combined transdermal acupoint electric stimulation (TAES) and isoflurane anesthesia. Isoflurane induced hypotension was performed in both groups by augmenting the concentration of isoflurane to lower the mean arterial pressure than before anesthesia for 30%-40% and maintain for 30-45 mins. The tissue oxygen metabolism, blood gas and arterial lactic acid level before, during and after hypotension were monitored by Swan-Ganz floating catheterization. Results: As compared with before hypotension, the pulmonary arterial and mixed with venous blood oxygen saturation lowered and oxygen supply lowered, and oxygen uptake increased significantly in both groups (P<0.05), but the extent of changes in oxygen metabolic criteria in Group B were all lesser than those in Group A (P<0.05). Conclusion: Combined acupoint electric stimulation and general anesthesia could maintain the tissue oxygen supply and demand balance better in the isoflurane-induced hypotension process.%目的:观察经皮穴位电刺激配合全麻在脑瘤术中行异氟醚控制性降压对患者组织氧代谢的影响。方法:选取ASA分级为Ⅰ~Ⅱ级的脑瘤择期手术患者42例,随机均分为两组。A组为常规全麻行异氟醚控制性降压;B组为经皮穴位电刺激配合全麻行异氟醚控制性降压。两组术中通过加大异氟醚浓度使平均动脉压较麻醉前下降30%~40%,维持30~45min。采用Swan-Ganz漂浮导管技术,对比监测降压前、中、后组织氧代谢及相应血气和动脉乳

  19. General Anesthesia Combined With Epidural Anesthesia on Elderly Patients With Single Lung Ventilation Intrapulmonary Shunt and Arterial Oxygenation%全麻复合硬膜外麻醉对老年患者单肺通气肺内分流及动脉氧合的影响

    Institute of Scientific and Technical Information of China (English)

    王福杰; 周英娟

    2016-01-01

    Objective Discuss on general anesthesia combined with epidural anesthesia on elderly patients with single lung ventilation pulmonary artery shunt and oxygenation.Methods Randomly selected from May 2013 to December 2015 in our hospital 60 elderly patients with clinical data,depending on the anesthesia,60 patients were divided into two groups, ]one group for the general anesthesia. Group 2 to 1.0% lidocaine anesthesia combined with epidural anesthesia group,30 cases in each. Compared the two groups before the single-lung ventilation lung,single lung ventilation 10 min,20 min,30 min, 40 min of arterial blood gases and arterial oxygenation.Results Arterial oxygen pressure and flow and ventilation points when comparing the two groups,had declined. Epidural anesthesia group decreased more efective than general anesthesia group,compared to the diference was statisticaly significant(P<0.05).Conclusion Anesthesia combined with epidural anesthesia in elderly patients with reduced single-lung ventilation pulmonary shunt,reduced arterial oxygen tension.%目的:探讨全麻复合硬膜外麻醉对老年患者单肺通气肺内分流及动脉氧合的影响。方法随机选择我院2013年5月~2015年12月我院收治的60例行开胸手术的老年患者临床资料,根据不同麻醉方式把60例患者分成2组,1组为全麻组,2组为全麻复合1.0%利多卡因硬膜外麻醉组,每组各30例。比较2组单肺肺通气前、单肺通气10 min、20 min、30 min、40 min的动脉血气及动脉氧合。结果两组单肺通气时动脉氧分压与分流量与通气前对比,均有所下降,全麻复合组下降效果优于单纯全麻组,对比差异有统计学意义(P<0.05)。结论全麻复合硬膜外麻醉减少老年患者单肺通气肺内分流,降低动脉血氧分压。

  20. 两种雾化吸入法在提高脑卒中肺部感染患者氧饱和度的效果观察%Effects of two atomizing inhalations on oxygen saturation of patients with stroke combined with pulmonary infections

    Institute of Scientific and Technical Information of China (English)

    史少凤; 李爱东; 邓雪萍

    2012-01-01

    Objective To compare the effects of ultrasonic atomizing inhalation and oxygen atomizing inhalation on SaO2 saturation of patients with stroke combined with pulmonary infections. Methods 62 patients with stroke combined with pulmonary infections were equally randomized into the observation group and the control group, which were managed with oxygen atomizing inhalation and ultrasonic atomizing inhalation, respectively. The two groups were compared in respect of SaO2. Result The mean level of SaO2 in the observation group was significantly higher than that of the control group (P < 0.01). Conclusion Oxygen atomizing inhalation is more effective both in the reduction of oxygen consumption in the patients with stroke combined with pulmonary infections and in the increase of SaO2.%目的 比较超声雾化吸入方法和氧驱动雾化吸入方法在提高脑卒中并发肺部感染患者氧饱和度(SaO2)中的作用效果.方法 选择62例脑卒中并发肺部感染患者,按入院确诊先后顺序分为观察组和对照组,每组各31例,分别采用超声雾化吸入方法和氧驱动雾化吸入方法.比较雾化吸入前后两组患者SaO2的差异.结果 雾化吸入治疗后观察组患者SaO2高于对照组,两组比较,P<0.01,差异具有统计学意义.结论 采用氧驱动雾化吸入可降低脑卒中并发肺部感染患者耗氧量,提高SaO2.

  1. Oxygen therapy - infants

    Science.gov (United States)

    ... may not work well and may die. Your baby may not grow properly. Many of the developing organs, including the brain and heart, may be injured. Too much oxygen can also cause injury. Breathing too much oxygen can damage the lung. ...

  2. Proterozoic atmospheric oxygen

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene

    2014-01-01

    This article is concerned with the evolution of atmospheric oxygen concentrations through the Proterozoic Eon. In particular, this article will seek to place the history of atmospheric oxygenation through the Proterozoic Eon in the context of the evolving physical environment including the histor...

  3. Highest Oxygen Bar

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The world’s highest altitude Lhalu Wetland in Tibet is rebounding from past environmental damage In Lhasa, where the oxygen content is just 60 percent of that of the plain area, a place known as the "natural oxygen bar"is highly prized by residents.

  4. Extracorporeal membrane oxygenation circuitry.

    Science.gov (United States)

    Lequier, Laurance; Horton, Stephen B; McMullan, D Michael; Bartlett, Robert H

    2013-06-01

    The extracorporeal membrane oxygenation circuit is made of a number of components that have been customized to provide adequate tissue oxygen delivery in patients with severe cardiac and/or respiratory failure for a prolonged period of time (days to weeks). A standard extracorporeal membrane oxygenation circuit consists of a mechanical blood pump, gas-exchange device, and a heat exchanger all connected together with circuit tubing. Extracorporeal membrane oxygenation circuits can vary from simple to complex and may include a variety of blood flow and pressure monitors, continuous oxyhemoglobin saturation monitors, circuit access sites, and a bridge connecting the venous access and arterial infusion limbs of the circuit. Significant technical advancements have been made in the equipment available for short- and long-term extracorporeal membrane oxygenation applications. Contemporary extracorporeal membrane oxygenation circuits have greater biocompatibility and allow for more prolonged cardiopulmonary support time while minimizing the procedure-related complications of bleeding, thrombosis, and other physiologic derangements, which were so common with the early application of extracorporeal membrane oxygenation. Modern era extracorporeal membrane oxygenation circuitry and components are simpler, safer, more compact, and can be used across a wide variety of patient sizes from neonates to adults.

  5. Imaging oxygen metabolism with hyperpolarized magnetic resonance

    DEFF Research Database (Denmark)

    Schroeder, Marie; Laustsen, Christoffer

    2017-01-01

    Every tissue in the body critically depends on meeting its energetic demands with sufficient oxygen supply. Oxygen supply/demand imbalances underlie the diseases that inflict the greatest socioeconomic burden globally. The purpose of this review is to examine how hyperpolarized contrast media, used...... in combination with MR data acquisition methods, may advance our ability to assess oxygen metabolism non-invasively and thus improve management of clinical disease. We first introduce the concept of hyperpolarization and how hyperpolarized contrast media have been practically implemented to achieve translational...... and clinical research. We will then analyze how incorporating hyperpolarized contrast media could enable realization of unmet technical needs in clinical practice. We will focus on imaging cardiac and renal oxygen metabolism, as both organs have unique physiological demands to satisfy their requirements...

  6. Therapeutic Effect of Hyperbaric Oxygen Treatment Combined Guided Periodontal Tissue Regeneration on Patients with Anterior Teeth Bone Deletion%高压氧联合GTR治疗前牙骨缺损疗效评价

    Institute of Scientific and Technical Information of China (English)

    周永庆; 何俐; 胡图强; 高晓燕; 郑钧元

    2014-01-01

    目的:评价高压氧(Hyperbaric oxygen,HBO)联合胶原膜引导组织再生术(Guided tissue regeneration,GTR)治疗前牙骨缺损效果.方法:将20例重度牙周病患者78颗下前牙骨缺损表面行胶原膜覆盖后随机分为单纯GTR组和HBO+ GTR组,分别于术前、术后6周、12周记录探诊深度(PD)、附着丧失(AL)、牙龈萎缩(RES)、牙龈指数(GI)、牙齿松动度(TM)、CBCT下新骨形成参数,并进行统计学分析.结果:HBO+ GTR组术后6周其缺损中央及边缘有新骨形成,骨密度增高,PD、AL和TM显著减少;RES和GI指数显著改善(P<0.05或P<0.01).但单纯GTR组直至12周后才逐渐有新骨形成.结论:高压氧联合胶原膜引导组织再生术能加快牙周组织恢复,加快缺损区骨密度增加及新骨形成.

  7. Effects of fluid restriction in combination with small dose of norepinephrine on cerebral oxygen metabolism in elderly patients undergoing gastrointestinal surgery%限制性输液复合小剂量去甲肾上腺素对胃肠道手术老年患者脑氧代谢的影响

    Institute of Scientific and Technical Information of China (English)

    邱晓东; 居斌华; 叶卉; 陆新健; 景亮; 汤文浩

    2015-01-01

    Objective To evaluate the effects of fluid restriction in combination with small dose of norepinephrine on cerebral oxygen metabolism in elderly patients undergoing gastrointestinal surgery.Methods Forty elderly patients of both sexes,aged 65-80 yr,with body mass index of 18-24 kg/m2,of ASA physical status Ⅰ or Ⅱ (NYHA Ⅰ or Ⅱ),with left ventricular ejection fraction≥50%,undergoing elective gastrointestinal surgery,were randomly divided into 2 groups (n =20 each) using a random number table:routine fluid administration group (group S) and restricted fluid administration + small dose of norepinephrine group (group RN).In group S,lactated Ringer's solution was given routinely,ephedrine 5 mg (per time) was injected intravenously,and MAP was maintained ≥ 65 mmHg during operation.In group RN,lactated Ringer's solution was infused intravenously at 5 ml · kg-1 · h-1 starting from 30 min before anesthesia,norepinephrine was infused intravenously at 0.01-0.03 μg · kg-1 · min-1 after induction of anesthesia,and MAP was maintained ≥ 65 mmHg.Intraoperative blood loss was replaced with the equal volume of 6% hydroxyethyl starch 130/0.4 sodium chloride injection in both groups.At 5 min before skin incision,1 and 2 h after skin incision and postanesthesia care unit discharge time,arterial and jugular bulb venous blood samples were obtained for blood gas analysis,and arterial oxygen content,jugular bulb venous oxygen content,arteriovenous oxygen content difference,cerebral oxygen extraction rate,and the ratio of cerebral blood flow to cerebral oxygen metabolic rate were calculated.Results There were no significant differences between the two groups in arterial oxygen content,jugular bulb venous oxygen content,arteriovenous oxygen content difference,cerebral oxygen extraction rate,and the ratio of cerebral blood flow to cerebral oxygen metabolic rate.Conclusion Fluid restriction combined with small dose of norepinephrine produces no effects on cerebral oxygen

  8. Oxygen foreshock of Mars

    Science.gov (United States)

    Yamauchi, M.; Lundin, R.; Frahm, R. A.; Sauvaud, J.-A.; Holmström, M.; Barabash, S.

    2015-12-01

    Mars Express (MEX) has operated for more than 10 years in the environment of Mars, providing solar wind ion observations from the Analyzer of Space Plasmas and Energetic Atoms experiment's Ion Mass Analyser (IMA). On 21 September 2008, MEX/IMA detected foreshock-like discrete distributions of oxygen ions at around 1 keV in the solar wind attached to the bow shock and this distribution was observed continuously up to more than 2000 km from the bow shock. Foreshock-like protons are also observed but at a shifted location from the oxygen by about 1000 km, at a slightly higher energy, and flowing in a slightly different direction than the oxygen ions. Both protons and oxygen ions are flowing anti-sunward at different angles with respect to the solar wind direction. This is the first time that a substantial amount of planetary oxygen is observed upstream of the bow shock. Although rare, this is not the only IMA observation of foreshock-like oxygen: oxygen ions are sometimes observed for a short period of time (<5 min) inside the foreshock region. These observations suggest a new escape channel for planetary ions through the acceleration in the bow shock-magnetosheath region.

  9. Clarification of the oxygen adsorption properties of YBaCo_4O_7 at high temperature by thermogravimetry

    Institute of Scientific and Technical Information of China (English)

    朱保峰; 郝好山; 张勇; 贾建峰; 胡行

    2010-01-01

    The oxygen adsorption/desorption properties of YBaCo4O7 at high temperature were investigated by thermogravimetry(TG) method,in which two types of oxygen adsorption were combined.The first type adsorbed oxygen at about 700 °C and released the adsorbed oxygen at 880 °C.After the first type oxygen desorption,even the temperature and oxygen flow were kept the same,a second type oxygen adsorption at about 880 °C occurred and the adsorbed oxygen were released at above 980 °C.The combination of these two types of...

  10. Cerebral Tissue Oxygenation during Immediate Neonatal Transition and Resuscitation

    Science.gov (United States)

    Pichler, Gerhard; Schmölzer, Georg M.; Urlesberger, Berndt

    2017-01-01

    This article provides a review of cerebral tissue oxygenation during immediate transition after birth in human neonates. Recommended routine monitoring, especially if resuscitation is needed, during this period includes arterial oxygen saturation and heart rate measured by pulse oximetry and electrocardiogram. However, there is increasing interest to monitor in addition with near-infrared spectroscopy (NIRS) the oxygenation of the brain. There is a different pattern of increase between cerebral tissue oxygenation and arterial oxygen saturation during the immediate transition, with cerebral tissue oxygenation reaching a plateau faster than arterial oxygen saturation. Differences can be explained, since cerebral tissue oxygenation is not only affected by arterial oxygen saturation but also by cerebral blood flow, hemoglobin content, and cerebral oxygen consumption. Normal values have already been established for different devices, gestational ages, and modes of delivery in neonates without any medical support. Cerebral hypoxia during immediate transition might cause brain damage. In preterm neonates with cerebral hemorrhage evolving in the first week after birth, the cerebral tissue oxygenation is already lower in the first minutes after birth compared to preterm neonates without cerebral hemorrhage. Using cerebral NIRS in combination with intervention guidelines has been shown to reduce the burden of cerebral hypoxia in preterm neonates. Cerebral tissue oxygenation during immediate transition seems to have an impact on outcome, whereby NIRS monitoring is feasible and has the advantage of continuous, non-invasive recording. The impact of NIRS monitoring and interventions on short- and long-term outcomes still need to be evaluated. PMID:28280719

  11. Microscopic oxygen imaging based on fluorescein bleaching efficiency measurements

    DEFF Research Database (Denmark)

    Beutler, Martin; Heisterkamp, Ines M.; Piltz, Bastian

    2014-01-01

    Photobleaching of the fluorophore fluorescein in an aqueous solution is dependent on the oxygen concentration. Therefore, the time-dependent bleaching behavior can be used to measure of dissolved oxygen concentrations. The method can be combined with epi-fluorescence microscopy. The molecular sta...... concentrations. The method was demonstrated on nitrifying biofilms growing on snail and mussel shells, showing clear effects of metabolic activity on oxygen concentrations. © 2014 Wiley Periodicals, Inc....

  12. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    David R. Thompson; Lawrence E. Bool; Jack C. Chen

    2004-04-01

    Conventional wisdom says adding oxygen to a combustion system enhances product throughput, system efficiency, and, unless special care is taken, increases NOx emissions. This increase in NOx emissions is typically due to elevated flame temperatures associated with oxygen use leading to added thermal NOx formation. Innovative low flame temperature oxy-fuel burner designs have been developed and commercialized to minimize both thermal and fuel NOx formation for gas and oil fired industrial furnaces. To be effective these systems require close to 100% oxy-fuel combustion and the cost of oxygen is paid for by fuel savings and other benefits. For applications to coal-fired utility boilers at the current cost of oxygen, however, it is not economically feasible to use 100% oxygen for NOx control. In spite of this conventional wisdom, Praxair and its team members, in partnership with the US Department of Energy National Energy Technology Laboratory, have developed a novel way to use oxygen to reduce NOx emissions without resorting to complete oxy-fuel conversion. In this concept oxygen is added to the combustion process to enhance operation of a low NOx combustion system. Only a small fraction of combustion air is replaced with oxygen in the process. By selectively adding oxygen to a low NOx combustion system it is possible to reduce NOx emissions from nitrogen-containing fuels, including pulverized coal, while improving combustion characteristics such as unburned carbon. A combination of experimental work and modeling was used to define how well oxygen enhanced combustion could reduce NOx emissions. The results of this work suggest that small amounts of oxygen replacement can reduce the NOx emissions as compared to the air-alone system. NOx emissions significantly below 0.15 lbs/MMBtu were measured. Oxygen addition was also shown to reduce carbon in ash. Comparison of the costs of using oxygen for NOx control against competing technologies, such as SCR, show that this

  13. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    la Cour, M; Kiilgaard, Jens Folke; Eysteinsson, T

    2000-01-01

    To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide....

  14. High Selectivity Oxygen Delignification

    Energy Technology Data Exchange (ETDEWEB)

    Lucian A. Lucia

    2005-11-15

    Project Objective: The objectives of this project are as follows: (1) Examine the physical and chemical characteristics of a partner mill pre- and post-oxygen delignified pulp and compare them to lab generated oxygen delignified pulps; (2) Apply the chemical selectivity enhancement system to the partner pre-oxygen delignified pulps under mill conditions (with and without any predetermined amounts of carryover) to determine how efficiently viscosity is preserved, how well selectivity is enhanced, if strength is improved, measure any yield differences and/or bleachability differences; and (3) Initiate a mill scale oxygen delignification run using the selectivity enhancement agent, collect the mill data, analyze it, and propose any future plans for implementation.

  15. De-oxygenation

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A; Kortzinger, A

    of fixed nitrogen that keeps the atmospheric nitrogen content constant over geological time scales. An important aspect of redox chemistry of nitrogen is the production of nitrous oxide (N2O), a potent greenhouse gas both as an intermediate during... denitrification and as a byproduct during the 30 oxidation of ammonium to nitrate (nitrification). Denitrification is confined to low-oxygen waters, but even during nitrification, the yield of N2O is greatly enhanced as the waters get depleted with oxygen...

  16. Observation on the therapeutic effect of Budesonide combined with Terbutaline inhalation via oxygen-driven atomization in treatment of 208 children capillarity bronchitis and nursing care%布地奈德联合特布他林气动雾化吸入治疗小儿毛细支气管炎208例疗效观察与护理

    Institute of Scientific and Technical Information of China (English)

    张家秀

    2012-01-01

    目的:探讨布地奈德联合特布他林气动雾化吸入治疗小儿毛细支气管炎的疗效与护理方法.方法:将312例毛细支气管炎患儿随机分为治疗组208例和对照组104例,对照组采用抗感染、止咳、平喘、化痰等综合性治疗,治疗组在此基础上加用布地奈德联合特布他林雾化液气动雾化吸入,比较两组疗效.结果:治疗组显效率高于对照组(P<0.05),喘憋及哮鸣音消失时间、住院时间短于对照组(P<0.01).结论:布地奈德联合特布他林气动雾化治疗毛细支气管炎能缩短病程,减轻患儿痛苦,减少并发症发生.%Objective: To investigate the therapeutic effect of Budesonide combined with Terbutaline inhalation via oxygen - driven at-omization in treatment of children capillarity bronchitis and nursing methods. Methods: 312 children patients with capillarity bronchitis were randomly divided into a treatment group( n = 208 )and a control group( n = 104 ). The comprehensive treatment like anti - infection, reliving cough and asthma and resolving phlegm was given to the patients in the control group and the patients in the treatment group received extra treatment with Budesonide combined with Terbutaline inhalation via oxygen - driven atomization based on the comprehensive treatment. The therapeutic effect was compared between the two groups. Results: The therapeutic effect in the treatment group was more efficient than the control group( P<0. 05 ); the disappearance time of breathlessness, wheezing and hospitalization time was shorter in the treatment group than the control group( P <0. 01 ). Conclusion: Budesonide combined with Terbutaline inhalation via oxygen - driven atomization in treatment of children capillarity bronchitis can shorten the course of disease, relieve childrens sufferings and reduce the occurrence of complications.

  17. 低温氧等离子体—壳聚糖对真丝织物的复合整理%Finishing of silk fabrics with the combination treatment of low-temperature oxygen plasma and chitosan

    Institute of Scientific and Technical Information of China (English)

    陈黎; 黄晨; 许云辉

    2012-01-01

    针对真丝织物易皱、抗菌性能差的问题,采用低温氧等离子体对真丝织物进行预处理,再用壳聚糖、柠檬酸溶液进行二浸二轧抗皱整理.对整理后的真丝织物进行力学性能和白度测试,探讨了有关工艺因素对整理效果的影响,确定了等离子体—壳聚糖对真丝织物抗皱整理的工艺.经整理后真丝织物的抗皱性能有较大提高,折皱回复角可提高50°左右,断裂强力和白度略有下降.结果表明,真丝织物经低温氧等离子体—壳聚糖联合整理后,壳聚糖与真丝纤维发生了接枝,故其折皱回复性能得以提高,纤维的结晶度有所下降.%For the poor wrinkle-resistant and poor antibacterial properties performance, silk fabrics were treated with low-temperature oxygen plasma before coordinated by chitosan-citric acid solution through double-dip-double-nip. The factors influenced on finishing results were studied and the anti-crease finishing process was obtained. The wrinkle-resistant properties of the finished fabrics were improved greatly and crease recovery angle could be improved more than 50°, while the breaking strength and the whiteness declined slightly. The results showed that the chemical crosslinking reaction occurred between chitosan and silk fiber when silk fabrics were carried out plasma-chitosan compound finishing, so the crease recovery performance was improved, and the crystallinity of the finished silk fabrics slightly decreased.

  18. Easy Fabrication of Dense Ceramic Membrane for Oxygen Separation

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A combined EDTA-citrate complexing method was developed for the easy preparation of mixed oxygen-ionic and electronic conducting dense ceramic membrane for oxygen separation.The new method takes the advantage of lower calcination temperature for phase formation, lower membrane sintering temperature and higher relative density over the standard ceramic method.

  19. Electric and electrochemical properties of catalytically active oxygen electrode materials

    NARCIS (Netherlands)

    Burggraaf, A.J.; Dijk, van M.P.; Vries, de K.J.

    1986-01-01

    The electrical conductivity has been investigated of some oxygen ion and mixed conducting materials. Electrodes are prepared from thin sputtered layers of these oxides combined with a small Au or Pt strip. The kinetics of the oxygen reaction has been studied for temperatures of 820–1020 K and PO2 va

  20. 高压氧联合高通量透析对肾性骨病患者血清骨形成蛋白-7表达及骨代谢的影响%Effects of Hyperbaric Oxygen Combined With High Flux Dialysis Formation Protein -7 Expression and Serum Bone on Bone Metabolism in Patients With Renal Osteodystrophy

    Institute of Scientific and Technical Information of China (English)

    张惠芳; 杨江成

    2015-01-01

    Objective To investigate the effects of hyperbaric oxygen combined with high lfux dialysis formation protein-7 expression and serum bone on bone metabolism in patients with renal osteodystrophy. Methods 104 cases of renal bone disease patients were randomly divided into treatment group (51 cases) and control group (53 cases) and given different treatment, compare the curative effect. Results The treatment group patients clinical effectiveness is significantly higher than control group (P<0.05), compared with the control group, treatment group serum phosphorus, iPTH value decreased significantly (P<0.05). Conclusion The effect of the hyperbaric oxygen combined high lfux dialysis mechanism may be the expression of BMP-7.%目的探讨高压氧联合高通量透析对肾性骨病患者血清骨形成蛋白-7表达及骨代谢的影响。方法将104例肾性骨病患者随机分为治疗组(51例)和对照组(53例),给予不同治疗,对比疗效。结果治疗组患者临床有效率高于对照组(P<0.05);与对照组相比,治疗组血清磷、iPTH值降低(P<0.05)。结论高压氧联合高通量透析产生的效果机制可能与BMP-7的表达有关。

  1. The effect observation of early hyperbaric oxygen combined music therapy on brain trauma coma wake and prognosis%早期高压氧联合音乐疗法对脑外伤昏迷促醒及预后的效果

    Institute of Scientific and Technical Information of China (English)

    黄的; 徐斌

    2016-01-01

    目的:观察早期高压氧联合音乐疗法对脑外伤昏迷促醒率及预后程度。方法:将170例脑外伤昏迷的患者,随机分为对照组和观察组,各85例。对照组给予常规药物治疗及康复护理,观察组在此基础上给予高压氧及音乐疗法,随访6个月,比较两组患者清醒时间及格拉斯哥预后结局量表(Glasgow outcome scale,GOS)等级情况。结果:两组患者的清醒时间及格拉斯哥预后结局等级比较,差异有统计学意义( P <0.05)。结论:早期高压氧联合音乐疗法对脑外伤昏迷促醒有较好的临床疗效,而且能减轻后遗症。%Objective:To observe the effect of early hyperbaric oxygen combined music therapy on brain trauma coma wake and prognosis. Nethods:170 cases of brain injury coma were randomly divided into control group(85 cases)and observation group(85cases). The control group was given conventional drugs and rehabilitation nursing,and the observation group with music therapy and hyperbaric oxygen treatment. After active treatment and follow - up for six months,the awake time,and Glasgow Outcome Scale for prognostic outcomes in the two groups were compared. Results:The comparison of awake time,and Glasgow Outcome Scale for prognostic outcomes between the two groups difference was statistically sig-nificant( P < 0. 05). Conclusion:Early hyperbaric oxygen combined music therapy on brain injury coma wake has better clinical curative effect, and can reduce sequel.

  2. Oxygen mass transfer in fermentation of bacillus thuringiensis

    Directory of Open Access Journals (Sweden)

    R. Ríos

    2011-12-01

    Full Text Available The purpose of this work was to obtain a correlation based on literature, depicting the relationships betwen the physical oxygen transfer rate (OTR and microbial oxygen uptake rate (OUR in order to determine the conditions (mass transfer coefficient, resulting on diferents combinations of aereations and agitations rates, under which growth will not be limited by oxygen. This correlation was adapted to culture with B. thuringiensis in order to estimate what biomass concentration are feasible for the physical limits set by operations conditions before microbial activity becomes limited by oxygen.

  3. Oxygen therapy reduces postoperative tachycardia

    DEFF Research Database (Denmark)

    Stausholm, K; Kehlet, H; Rosenberg, J

    1995-01-01

    Concomitant hypoxaemia and tachycardia in the postoperative period is unfavourable for the myocardium. Since hypoxaemia per se may be involved in the pathogenesis of postoperative tachycardia, we have studied the effect of oxygen therapy on tachycardia in 12 patients randomly allocated to blinded...... air or oxygen by facemask on the second or third day after major surgery. Inclusion criteria were arterial hypoxaemia (oxygen saturation 90 beat.min-1). Each patient responded similarly to oxygen therapy: an increase in arterial oxygen saturation and a decrease...... in heart rate (p oxygen has a positive effect on the cardiac oxygen delivery and demand balance....

  4. Use of Optical Oxygen Sensors in Non-Destructively Determining the Levels of Oxygen Present in Combined Vacuum and Modified Atmosphere Packaged Pre-Cooked Convenience-Style Foods and the Use of Ethanol Emitters to Extend Product Shelf-Life

    Directory of Open Access Journals (Sweden)

    Andreas W. Hempel

    2013-11-01

    Full Text Available O2 sensors were used to non-destructively monitor O2 levels in commercially packed pre-cooked, convenience modified atmosphere packaging (MAP foods. A substantial level of O2 (>15% was present in packs resulting in a shorter than expected shelf-life, where the primary spoilage mechanism was found to be mould. Various combinations of vacuum (0–0.6 MPa and gas flush (0.02–0.03 MPa (30% CO2/70% N2 settings were assessed as treatments that result in the desired shelf-life (28 days. This was achieved using the combined treatment of vacuum 0.35 MPa and gas flush 0.02 MPa which resulted in a reduction of 6%–9% O2 in all three samples (battered sausages (BS, bacon slices (BA, and meat and potato pies (PP. Reduced O2 levels reflect the microbial quality of products, which has been successfully reduced. Duplicate samples of all product packs were produced using ethanol emitters (EE to see if shelf-life could be further extended. Results showed a further improvement in shelf-life to 35 days. Sensory analysis showed that ethanol flavour and aroma was not perceived by panellists in two of the three products assessed. This study demonstrates how smart packaging technologies, both intelligent and active, can be used to assist in the modification of conventional packaging systems in order to enhance product quality and safety and through the extension of product shelf-life.

  5. Study on the application of hyperbaric oxygen combined with iodized lecithin in the treatment of central serous chorioretinopathy%中心性浆液性脉络膜视网膜病变患者应用高压氧联合卵磷脂络合碘治疗的研究

    Institute of Scientific and Technical Information of China (English)

    张娜

    2015-01-01

    目的:分析中心性浆液性脉络膜视网膜病变(CSC)患者应用高压氧联合卵磷脂络合碘治疗的临床疗效及安全性。方法随机选取2012年12月~2013年12月本院诊治的98例(108眼)中心性浆液性脉络膜视网膜病变患者,按照随机双盲法分为两组,对照组49例予以高压氧治疗,研究组49例在对照组基础上联合卵磷脂络合碘治疗,分析两组患者视力恢复及不良反应情况。结果两组患者治疗后视力均明显恢复,且研究组患者的视力明显优于对照组,比较差异均具有统计学意义(P<0.05),研究组治疗后复发情况明显少于对照组,比较差异具有统计学意义(P<0.05);同时,两组患者的不良反应情况比较差异不明显,且均经临床对症治疗后缓解。结论应用高压氧联合卵磷脂络合碘治疗中心性浆液性脉络膜视网膜病变的临床疗效显著,且用药过程安全可靠。%Objective To analyze the clinical efficacy and safety of hyperbaric oxygen combined with iodized lecithin in the treatment of central serous chorioretinopathy(CSC).Methods 98 cases(108 eyes) of patients with central serous chorioretinopathy in our hospital from December 2012 to December 2013 were randomly selected, which according to the randomized double blind method were divided into two groups, each with 49 cases. While the 49 cases of patients in the control group were given hyperbaric oxygen therapy, the 49 cases in the study group were treated with hyperbaric oxygen combined with iodized lecithin. The recovery of visual acuity and adverse reaction of the two groups were analyzed.Results After the treatment, visual acuity of patients in both the two groups were significantly restored, and that of the study group was significantly better than the control group, with statistically significant difference(P<0.05). Recurrence in the study group was significantly less than the control group after the

  6. Effect of Inhalation of Nitrous Oxide/Oxygen Mixture Combined with Lornoxicam on Wound Pain after Burn Injury%氧化亚氮/氧气混合气体吸入联合氯诺昔康用于烧伤后创面疼痛的疗效

    Institute of Scientific and Technical Information of China (English)

    付小花; 蔡爱英; 张爱萍; 彭燕

    2014-01-01

    目的:观察氧化亚氮/氧气混合气体吸入联合氯诺昔康用于烧伤后创面疼痛的临床疗效。方法将48例烧伤后创面疼痛的患者按治疗方法的不同分为2组:观察组(23例)和对照组(25例)。2组均采用注射用氯诺昔康8 mg加入0.9%氯化钠注射液100 mL中静脉滴注,2次·d-1。在此基础上,观察组采用Digital MDM氧化亚氮/氧气混合输出系统治疗。观察2组临床疗效的情况,并对2组进行目测类比疼痛评分(VAS评分)和疼痛问卷评分(疼痛感觉评分和疼痛情绪评分)。结果观察组总有效率明显高于对照组(91.3%比76.0%,P<0.05);与对照组比较,观察组治疗1 d后VAS、疼痛感觉和疼痛情绪得分均明显降低(均P<0.05)。结论氧化亚氮/氧气混合气体吸入联合氯诺昔康用于烧伤后创面疼痛有较好的镇痛效果,且无明显的不良反应。%Objective To observe the clinical effect of inhalation of nitrous oxide/oxygen mixture combined with lornoxicam on wound pain after burn injury. Methods Forty-eight patients with burn injury pain were divided into observation group(n=23) and control group(n=25). All patients were given 8 mg lornoxicam dissolved in 100 mL 0.9% sodium chloride injection via intravenous drip twice per day. In addition, patients in observation group were treated with the Digital MDM nitrous oxide/oxygen mixer . Clinical effects were observed and visual analogue scale ( VAS ) scores and pain questionnaire scores ( feeling and emotional pain scores ) were determined in both groups . Results Compared with control group,the inhalation of nitrous oxide/oxygen mixture combined with intravenous lornoxicam administration significantly increased the overall response rate ( 91 . 3% vs 76 . 0%, P<0 . 05 ) , and obviously decreased VAS , feeling pain and emotional scores after treatment for 1 day ( P<0 . 05 ) . Conclusion The inhalation of nitrous oxide/oxygen mixture combined

  7. Oxygen ion conductors

    Directory of Open Access Journals (Sweden)

    Stephen J Skinner

    2003-03-01

    A very interesting subgroup of this class of materials are the oxides that display oxygen ion conductivity. As well as the intrinsic interest in these materials, there has been a continued drive for their development because of the promise of important technological devices such as the solid oxide fuel cell (SOFC, oxygen separation membranes, and membranes for the conversion of methane to syngas1. All of these devices offer the potential of enormous commercial and ecological benefits provided suitable high performance materials can be developed. In this article we will review the materials currently under development for application in such devices with particular reference to some of the newly discovered oxide ion conductors.

  8. Neurological oxygen toxicity.

    Science.gov (United States)

    Farmery, Scott; Sykes, Oliver

    2012-10-01

    SCUBA diving has several risks associated with it from breathing air under pressure--nitrogen narcosis, barotrauma and decompression sickness (the bends). Trimix SCUBA diving involves regulating mixtures of nitrogen, oxygen and helium in an attempt to overcome the risks of narcosis and decompression sickness during deep dives, but introduces other potential hazards such as hypoxia and oxygen toxicity convulsions. This study reports on a seizure during the ascent phase, its potential causes and management and discusses the hazards posed to the diver and his rescuer by an emergency ascent to the surface.

  9. Analytical theory of oxygen transport in the human placenta.

    Science.gov (United States)

    Serov, A S; Salafia, C M; Filoche, M; Grebenkov, D S

    2015-03-07

    We propose an analytical approach to solving the diffusion-convection equations governing oxygen transport in the human placenta. We show that only two geometrical characteristics of a placental cross-section, villi density and the effective villi radius, are needed to predict fetal oxygen uptake. We also identify two combinations of physiological parameters that determine oxygen uptake in a given placenta: (i) the maximal oxygen inflow of a placentone if there were no tissue blocking the flow and (ii) the ratio of transit time of maternal blood through the intervillous space to oxygen extraction time. We derive analytical formulas for fast and simple calculation of oxygen uptake and provide two diagrams of efficiency of oxygen transport in an arbitrary placental cross-section. We finally show that artificial perfusion experiments with no-hemoglobin blood tend to give a two-orders-of-magnitude underestimation of the in vivo oxygen uptake and that the optimal geometry for such setup alters significantly. The theory allows one to adjust the results of artificial placenta perfusion experiments to account for oxygen-hemoglobin dissociation. Combined with image analysis techniques, the presented model can give an easy-to-use tool for prediction of the human placenta efficiency.

  10. Oxygen dynamics and transport in the Mediterranean sponge Aplysina aerophoba

    DEFF Research Database (Denmark)

    Hoffmann, F.; Røy, Hans; Bayer, K.;

    2008-01-01

    The Mediterranean sponge Aplysina aerophoba kept in aquaria or cultivation tanks can stop pumping for several hours or even days. To investigate changes in the chemical microenvironments, we measured oxygen profiles over the surface and into the tissue of pumping and non-pumping A. aerophoba...... specimens with Clark-type oxygen microelectrodes (tip diameters 18-30 μm). Total oxygen consumption rates of whole sponges were measured in closed chambers. These rates were used to back-calculate the oxygen distribution in a finite-element model. Combining direct measurements with calculations of diffusive...... flux and modeling revealed that the tissue of non-pumping sponges turns anoxic within 15 min, with the exception of a 1 mm surface layer where oxygen intrudes due to molecular diffusion over the sponge surface. Molecular diffusion is the only transport mechanism for oxygen into non-pumping sponges...

  11. Effect of an oxygen pressure injection (OPI) device on the oxygen saturation of patients during dermatological methyl aminolevulinate photodynamic therapy.

    Science.gov (United States)

    Blake, E; Allen, J; Thorn, C; Shore, A; Curnow, A

    2013-05-01

    Methyl aminolevulinate photodynamic therapy (MAL-PDT) (a topical treatment used for a number of precancerous skin conditions) utilizes the combined interaction of a photosensitizer (protoporphyrin IX (PpIX)), light of the appropriate wavelength, and molecular oxygen to produce singlet oxygen and other reactive oxygen species which induce cell death. During treatment, localized oxygen depletion occurs and is thought to contribute to decreased efficacy. The aim of this study was to investigate whether an oxygen pressure injection (OPI) device had an effect on localized oxygen saturation levels and/or PpIX fluorescence of skin lesions during MAL-PDT. This study employed an OPI device to apply oxygen under pressure to the skin lesions of patients undergoing standard MAL-PDT. Optical reflectance spectrometry and fluorescence imaging were used to noninvasively monitor the localized oxygen saturation and PpIX fluorescence of the treatment area, respectively. No significant changes in oxygen saturation were observed when these data were combined for the group with OPI and compared to the group that received standard MAL-PDT without OPI. Additionally, no significant difference in PpIX photobleaching or clinical outcome at 3 months between the groups of patients was observed, although the group that received standard MAL-PDT demonstrated a significant increase (pMAL-PDT. Further investigation is therefore required to find a more effective method of MAL-PDT enhancement.

  12. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    Kiilgaard, Jens Folke; Pedersen, D B; Eysteinsson, T

    2004-01-01

    The authors have previously reported that carbonic anhydrase inhibitors such as acetazolamide and dorzolamide raise optic nerve oxygen tension (ONPO(2)) in pigs. The purpose of the present study was to investigate whether timolol, which belongs to another group of glaucoma drugs called beta block...

  13. Aircraft Oxygen Generation

    Science.gov (United States)

    2012-02-01

    aircraft use some form of on-board oxygen generation provided by one of two corporations that dominate this market . A review of safety incident data...manufacture of synthetic resins (e.g., Bakelite), and for 161 making dyestuffs, flavorings, perfumes , and other chemicals. Some are used as

  14. Oxygenated Derivatives of Hydrocarbons

    Science.gov (United States)

    For the book entitled “Insect Hydrocarbons: Biology, Biochemistry and Chemical Ecology”, this chapter presents a comprehensive review of the occurrence, structure and function of oxygenated derivatives of hydrocarbons. The book chapter focuses on the occurrence, structural identification and functi...

  15. Hybrid Oxygen System

    Science.gov (United States)

    1992-10-01

    otherwise in any manner construed, as licensing the holder or any other person or corporation ; or as conveying any rights or permission to manufacture, use...12 Modest Activity 2 12 24 Comnat ane G’s Average 5 32 64 Peak Activity (NATO) 10 50 Instantaneous Peak Flow N/A 150-20W_ Published oxygen flow rates

  16. Observation on the Effect of Early Massage Combined with Hyperbaric Oxygen or Hydrotherapy on Recent Nerve Motor Function of Severe Neonatal HIE%早期抚触联合高压氧或水疗对重度新生儿缺氧缺血性脑病近期神经运动功能的影响

    Institute of Scientific and Technical Information of China (English)

    常文更

    2014-01-01

    To explore the effect of early massage combined hyperbaric oxygen therapy ,hydro-therapy on recent nerve motor function of severe neonatal hypoxic-ischemic encephalopathy(HIE) .[Methods]Totally 497 patients with HIE were collected .According to the treatment methods ,all patients were divided into group A ,B and C .Group A received simple early massage ,and group B received massage combined with hyperbaric oxygen therapy ,and group C received massage combined with hydrotherapy .Motor function ,nerve 20-item score criteria(NBNA) score ,body weight ,height ,daily milk intake after treatment were compared a-mong 3 groups .[Results]After treatment ,the proportion of taking grade Ⅲ action in group A was obviously lower than that in group B and group C( P 0 .05) .NBNA scores in group B and group C at 2 and 4 weeks after treatment were signifi-cantly higher than those in group A ( P 0 .05) .The weight ,height and daily milk intake in group B and group C at 4 weeks after treatment were significantly better than group A ( P 0 .05) .[Conclusion]Early massage combined with hyperbaric oxygen or hydrotherapy can promote neural motor function rehabilitation in pediatric patients with HIE and is condu-cive to neonatal growth and development .Therefore ,it is worthy of clinical promotion .%【目的】探讨早期抚触联合高压氧疗、水疗对重度新生儿缺氧缺血性脑病(HIE)近期神经运动功能的影响。【方法】收集 H IE患儿497例,按照治疗方法分为A、B、C三组,A组采用单纯早期抚触,B组抚触联合高压氧疗,C组采用抚触联合水疗。对比三组患儿运动功能、神经20项评分标准(NBNA )评分及治疗后体质量、身高、每日摄奶量情况。【结果】治疗后A组完成Ⅲ级动作比例明显低于B组和C组( P <0.05),其中B组与C组相比差异无统计学意义( P>0.05);治疗2周、4周后B组、C组NBNA评分显著高于A组( P<0.05),其中B、C两组间

  17. Oxygen Extraction from Minerals

    Science.gov (United States)

    Muscatello, Tony

    2017-01-01

    Oxygen, whether used as part of rocket bipropellant or for astronaut life support, is a key consumable for space exploration and commercialization. In Situ Resource Utilization (ISRU) has been proposed many times as a method for making space exploration more cost effective and sustainable. On planetary and asteroid surfaces the presence of minerals in the regolith that contain oxygen is very common, making them a potential oxygen resource. The majority of research and development for oxygen extraction from minerals has been for lunar regolith although this work would generally be applicable to regolith at other locations in space. This presentation will briefly survey the major methods investigated for oxygen extraction from regolith with a focus on the current status of those methods and possible future development pathways. The major oxygen production methods are (1) extraction from lunar ilmenite (FeTiO3) with either hydrogen or carbon monoxide, (2) carbothermal reduction of iron oxides and silicates with methane, and (3) molten regolith electrolysis (MRE) of silicates. Methods (1) and (2) have also been investigated in a two-step process using CO reduction and carbon deposition followed by carbothermal reduction. All three processes have byproducts that could also be used as resources. Hydrogen or carbon monoxide reduction produce iron metal in small amounts that could potentially be used as construction material. Carbothermal reduction also makes iron metal along with silicon metal and a glass with possible applications. MRE produces iron, silicon, aluminum, titanium, and glass, with higher silicon yields than carbothermal reduction. On Mars and possibly on some moons and asteroids, water is present in the form of mineral hydrates, hydroxyl (-OH) groups on minerals, andor water adsorbed on mineral surfaces. Heating of the minerals can liberate the water which can be electrolyzed to provide a source of oxygen as well. The chemistry of these processes, some key

  18. Oxygen consumption by a coral reef sponge.

    Science.gov (United States)

    Hadas, Eran; Ilan, Micha; Shpigel, Muki

    2008-07-01

    Oxygen consumption of the Red Sea coral reef sponge Negombata magnifica was measured using both incubation and steady-state methods. The latter method was found to be the more reliable because sponge activity remained stable over time. Oxygen consumption rate was measured during three levels of sponge activity: full activity, reduced activity and basal activity (starved). It was found that the active oxygen consumption rate of N. magnifica averaged 37.3+/-4.6 nmol O2 min(-1) g(-1) wet mass, which is within the upper range reported for other tropical marine sponges. Fully active N. magnifica individuals consumed an average of 41.8+/-3.2 nmol O2 min(-1) g(-1) wet mass. The mean basal respiration rate was 20.2+/-1.2 nmol O2 min(-1) g(-1) wet mass, which is 51.6+/-2.5% of the active respiration rate. Therefore, the oxygen used for water pumping was calculated to be at most 10.6+/-1.8 nmol O2 min(-1) g(-1) wet mass, which is 25.1+/-3.6% of the total respiration. Combined oxygen used for maintenance and water pumping activity was calculated to be 30.8 nmol O2 min(-1) g(-1) wet mass, which is approximately 74% of the sponge's total oxygen requirement. The remaining oxygen is directed to other physiological activities, mainly the energy requirement of growth. These findings suggest that only a relatively minor amount of energy is potentially available for growth, and thus might be a factor in controlling the growth rate of N. magnifica in oligotrophic coral reefs.

  19. Turbulent Oxygen Flames in Type Ia Supernovae

    CERN Document Server

    Aspden, A J; Woosley, S E; 10.1088/0004-637X/730/2/144

    2011-01-01

    In previous studies, we examined turbulence-flame interactions in carbon-burning thermonuclear flames in Type Ia supernovae. In this study, we consider turbulence-flame interactions in the trailing oxygen flames. The two aims of the paper are to examine the response of the inductive oxygen flame to intense levels of turbulence, and to explore the possibility of transition to detonation in the oxygen flame. Scaling arguments analogous to the carbon flames are presented and then compared against three-dimensional simulations for a range of Damk\\"ohler numbers ($\\Da_{16}$) at a fixed Karlovitz number. The simulations suggest that turbulence does not significantly affect the oxygen flame when $\\Da_{16}1$, turbulence enhances heat transfer and drives the propagation of a flame that is {\\em narrower} than the corresponding inductive flame would be. Furthermore, burning under these conditions appears to occur as part of a combined carbon-oxygen turbulent flame with complex compound structure. The simulations do not ...

  20. Oxygen treatment of cluster headache

    DEFF Research Database (Denmark)

    Petersen, Anja S; Barloese, Mads C J; Jensen, Rigmor H

    2014-01-01

    of oxygen treatment. One study is observational and the remaining five are RCTs. Another five studies were on hyperbaric oxygen treatment hereof two case studies. CONCLUSION: Oxygen therapy can be administered at different flow rates. Three studies investigate the effect of low-flow oxygen, 6-7 l....../min, and found a positive response in 56%, 75% and 82%, respectively, of the patients. One study investigates high-flow oxygen, 12 l/min, and found efficacy in 78% of attacks. The effect of hyperbaric oxygen therapy has been investigated in a few small studies and there is evidence only for an acute...

  1. Analysis of On-Board Oxygen and Nitrogen Generation Systems for Surface Vessels.

    Science.gov (United States)

    1983-06-01

    microfiltration , combined with a capability of a molecular-sized reaction vessel and ion exchanger. Utilization of membrane fil- ters varies from...Fluomine Sorbent Oxygen Generating Process . . . . . . . . . . . .. .. . . . . . . . . 13 7 Theory of Operation of Liquid Membrane , Producing Oxygen from...Commercial requirements for oxygen include more than 10 major industrial sectors ; among them are steel and oil production, envi- ronmental protection, and

  2. RELATIONS OF THE CEREBRAL OXYGEN METABOLISM AND THE COGNITIVE FUNCTION AFTER COMBINED DEXMEDETOMIDINE ANESTHESIA OPERATION IN ELDERLY PATIENTS%右美托咪定联合全麻下老年患者术后认知功能与脑氧代谢的关系

    Institute of Scientific and Technical Information of China (English)

    吕安庆; 陈文迪

    2012-01-01

    目的 探讨右美托咪定联合全麻下老年患者术后认知功能与脑氧代谢的关系.方法 选取2009年12月-2011年6月期间在全身麻醉下行手术的老年患者100例,美国麻醉医师协会分级Ⅰ~Ⅲ级.随机分为2组,治疗组和对照组,各50例,采用简易智力状态检查表(mini-mental state examination,MMSE)对比评估2组患者术后6h,1、3d的认知功能.2组于麻醉诱导后即刻(T0 )、麻醉后60min(T1) 和麻醉恢复时(T2) 同步采集桡动脉和颈内静脉球部血样行血气分析,根据血红蛋白(hemoglobin,Hb)、动脉血氧饱和度(arterial oxygen saturation,SaO2)、颈内静脉血氧饱和度(jugular venous oxygen saturation,SjvO2)、动脉血氧分压(arterial partial prussure of oxygen,PaO2) 和颈内静脉血氧分压(jugular venous oxygen partial pressure,PjvO2),计算脑血流量/脑氧代谢率比值(cerebral blood flow to cerebral metabolic rate for oxygen,CBF/CMRO2).结果 手术后6h、1d各组MMSE评分均有不同程度的降低(P<0.05);手术后6h、1d A组MMSE评分明显低于B组(P<0.05);A组T0和T1时,CBF/CMR02异常发生率明显降低,差异有统计学意义(P<0.05); Logistic逐步回归分析显示T1时CBF/CMRO2异常与老年患者术后认知功能障碍的发生有关(β=3.413,P<0.05).结论 全麻下老年患者脑氧代谢异常可能是认知功能障碍的诱导原因之一,右美托咪定可能通过调节脑氧代谢功能来改善术后认知功能.%Objective To investigate the relations of the cerebral oxygen metabolism and the cognitive function after combined dexmedetomidine anesthesia operation in elderly patients. Methods One hundred patients aged over 60 years old were randomly divided into two groups: treatment group ( n = 50 ) and control group ( n = 50 ). A battery of mini - mental state examination ( MMSE ) and neuropsychological tests were administered 6 hours, 1 day and 7 days after surgery. Blood samples were taken from artery and internal jugular

  3. Curative effecive observation of incontinence dermatitis using oxygen therapy combined with stoma powder and Algoplaque%氧疗联合造口粉及安普贴的使用治疗失禁性皮炎疗效观察

    Institute of Scientific and Technical Information of China (English)

    韩雪飞; 黄莉莎; 陈文姿; 云燕

    2015-01-01

    ObjectiveTo observe the clinical curative effect of oxygen therapy combined with stoma powder and Algoplaque in treatment of incontinence dermatitis.Methods80 cases of incontinence dermatitis patients admitted in our hospital from January 2013 to October 2014 as the research object, were randomly divided into two groups, patients in control group were treated with ostomy powder +3M wound protective membrane treatment, patients in observation group was for oxygen therapy combined with stoma powder and Algoplaque treatment, compared two groups of clinical curative effect and nursing time and healing time.Results In the observation group, the cure rate and total effective rate was 100.00%, there was statistically significant difference in the control group 82.50%, 90.00% (P<0.05). Average care time of two groups [(2.35±1.05)d VS(4.45±1.34)d], nursing times [(1.51±0.60)times VS(11.40±2.78)times] and healing time [(2.78±1.00)d VS(4.69±0.88)d]were significantly different (P<0.05). In ad dition, the incidence in observation group was significantly less than control group (P<0.05).Conclusion The effect of oxygen therapy combined with stoma powder and Algoplaque in treatment of incontinence dermatitis is clear, can effectively shorten the healing time, reduce the nursing workload, is worth the clinical promotion.%目的:观察氧疗联合造口粉及安普贴治疗失禁性皮炎的临床疗效。方法以我院2013年1月~2014年10月收治的80例失禁性皮炎患者为研究对象,随机将其分为两组,对照组患者给予造口粉+3M伤口保护膜治疗,观察组患者则行氧疗联合造口粉及安普贴治疗,比较两组临床疗效、护理时间、护理次数及愈合时间。结果观察组治愈率、总有效率均为100.00%,与对照组的82.50%、90.00%比较,差异有统计学意义(P<0.05)。两组平均护理时间[(2.35±1.05)d VS(4.45±1.34)d]、护理次数[(1.51±0.60)次VS (11.40±2.78

  4. The efficacy of hyperbaric oxygen combined with Xingnaojing injection in the treatment of viral meningitis in children%高压氧联合醒脑静注射液对小儿病毒性脑膜炎的疗效

    Institute of Scientific and Technical Information of China (English)

    林传琼

    2015-01-01

    目的:探讨高压氧联合醒脑静注射液对小儿病毒性脑膜炎运动功能及智力发育的影响。方法:选取我院收治的小儿病毒性脑膜炎患儿68例,随机分为观察组和对照组各34例,观察组给予高压氧联合醒脑静注射液治疗,对照组仅给予醒脑静注射液治疗。比较两组患儿运动功能及智力发育的改善情况。结果:两组患者治疗后上肢、下肢 FMA评分较治疗前均有明显改善,且观察组优于对照组;两组患者5个功能区发育商均有改善,观察组精细动作、适应能力、语言和社交能力发育商明显高于对照组。差异均有统计学意义。结论:高压氧联合醒脑静注射液治疗小儿病毒性脑膜炎,可明显提高患儿的运动功能及智力发育,提高生活质量。%Objective: To investigate the efficacy of hyperbaric oxygen combined with Xingnaojing injection on the motor function and intelligence development of children with viral meningitis. Methods: Sixty-eight cases of children with viral meningitis in our hospital were randomly divided into an observation group and a control group with 34 cases each. Hyperbaric oxygen combined with Xingnaojing injection was given in the observation group while only Xingnaojing injection in the control group. The improvement of motor function and intelligence development were compared between two groups. Results: The FMA scores for upper and lower limbs in two groups were significantly improved after the treatment, and were much higher in the observation group than in the control group. The developmental quotient (DQ) of 5 function areas was all improved, however, DQ of fine motor, adaptive capacity, language and social skills was significantly higher in the observation group than in the control group. All the differences were statistically significant. Conclusion: Hyperbaric oxygen combined with Xingnaojing injection in the treatment of children with viral meningitis can

  5. 高压氧联合甲钴胺治疗2型糖尿病周围神经病变的临床效果研究%Clinical effects of hyperbaric oxygen combined with mecobalamine on patients with type 2 diabetic peripheral neuropathy

    Institute of Scientific and Technical Information of China (English)

    汤涌; 张红梅

    2012-01-01

    目的 研究高压氧联合甲钴胺治疗糖尿病周围神经病变的临床疗效.方法 临床入选142例2型糖尿病周围神经病变患者,对入选患者按照入院时间先后进行编号,分为对照组和研究组,每组71例,两组均采取严格控制血糖治疗,其中对照组加用甲钴胺治疗,而研究组在对照组的基础上,加用高压氧治疗.随访和分析两组的感觉神经及运动神经的传导速度、H反应潜伏期、血液生化指标以及综合疗效评估等临床资料.结果 在治疗后,研究组的运动神经和感觉神经的传导速度较对照组明显增快(P<0.05),胆固醇、甘油三脂、血浆黏度、全血低切还原黏度以及随机血糖水平均较对照组明显改善(P<0.05);对照组的总有效率为63.38%,研究组的总有效率为85.92%,两组之间具有统计学差异(P<0.05).结论 缺血缺氧是糖尿病周围神经病变的主要病理改变,高压氧联合甲钴胺对其具有较好的治疗效果.%Objective To investigate the clinical curative effects of hyperbaric oxygen combined with mecobalamine on patients with type 2 diabetic peripheral neuropathy( DPN ). Methods The 142 clinically selected patients with type 2 DPN were divided into control group and research group with 71 people in each group. Both groups received strict treatment regimen to control blood sugar. Meanwhile the control group received the treatment with mecobalamine,and the research group received hyperbaric oxygen combined with mecobalamine. Follow - up and analysis were made in clinical data of both groups,such as conduction velocity of sensory and motor nerves, H reaction latency, blood biochemical indicators and integrative curative effects. Results After the treatment, the conduction velocity of sensory and motor nerves in the research group increased significantly compared with those in the control group ( P <0. 05 ). Compared with the control group, the cholesterol, triglyceride, plasma viscosity

  6. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-02-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. The in situ electrical conductivity and Seebeck coefficient measurements were made on LSFT at 1000 and 1200 C over the oxygen activity range from air to 10{sup -15} atm. The electrical conductivity measurements exhibited a p to n type transition at an oxygen activity of 1 x 10{sup -10} at 1000 C and 1 x 10{sup -6} at 1200 C. Thermogravimetric studies were also carried out over the same oxygen activities and temperatures. Based on the results of these measurements, the chemical and mechanical stability range of LSFT were determined and defect structure was established. The studies on the fracture toughness of the LSFT and dual phase membranes exposed to air and N{sub 2} at 1000 C was done and the XRD and SEM analysis of the specimens were carried out to understand the structural and microstructural changes. The membranes that are exposed to high temperatures at an inert and a reactive atmosphere undergo many structural and chemical changes which affect the mechanical properties. A complete transformation of fracture behavior was observed in the N{sub 2} treated LSFT samples. Further results to investigate the origin of the slow kinetics on reduction of ferrites have been obtained. The slow kinetics appear to be related to a non-equilibrium reduction pathway that initially results in the formation of iron particles. At long times, equilibrium can be reestablished with recovery of the perovskite phase. Recent results on transient kinetic data are presented. The 2-D modeling of oxygen movement has been undertaken in order to fit isotope data. The model is used to study ''frozen'' profiles in patterned or composite membranes.

  7. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-08-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In the previous research, the reference point of oxygen occupancy was determined and verified. In the current research, the oxygen occupancy was investigated at 1200 C as a function of oxygen activity and compared with that at 1000 C. The cause of bumps at about 200 C was also investigated by using different heating and cooling rates during TGA. The fracture toughness of LSFT and dual phase membranes at room temperature is an important mechanical property. Vicker's indentation method was used to evaluate this toughness. Through this technique, a K{sub Ic} (Mode-I Fracture Toughness) value is attained by means of semi-empirical correlations between the indentation load and the length of the cracks emanating from the corresponding Vickers indentation impression. In the present investigation, crack propagation behavior was extensively analyzed in order to understand the strengthening mechanisms involved in the non-transforming La based ceramic composites. Cracks were generated using Vicker's indenter and used to identify and evaluate the toughening mechanisms involved. Preliminary results of an electron microscopy study of the origin of the slow kinetics on reduction of ferrites have been obtained. The slow kinetics appear to be related to a non-equilibrium reduction pathway that initially results in the formation of iron particles. At long times, equilibrium can be reestablished with recovery of the perovskite phase. Modeling of the isotopic transients on operating membranes (LSCrF-2828 at 900 C) and a ''frozen'' isotope profile have been analyzed in conjunction with a 1-D model to reveal the gradient in oxygen diffusivity through the membrane under conditions of high chemical gradients.

  8. 普米克令舒联合博利康尼氧气雾化吸入治疗毛细支气管炎120例%Pulmicort combined Bricanyl inhalation of oxygen in treatment of bronchiolitis 120 cases

    Institute of Scientific and Technical Information of China (English)

    闫伯强

    2011-01-01

    目的 观察普米克联合博利康尼以氧气作动力雾化吸入治疗毛细支气管炎的疗效.方法 将240例毛细支气管炎患儿随机分为两组,观察组120例在常规治疗的基础上辅以普米克令舒联合博利康尼氧驱雾化吸入;对照组120例仅进行常规治疗.结果 观察组咳喘消失时间、肺部湿啰音消失时间和住院时间均优于对照组(P<0.05),观察组总有效率91.7%,对照组总有效率55%,两组疗效差异有统计学意义(P<0.05).结论 普米克令舒联合博利康尼治疗小儿毛细支气管炎的临床疗效确切,值得临床推广使用.%Objective To observe the effect of Pulmicort combined Bricanyl with oxygen inhalation therapy for bronchiolitis. Methods Totally 240 patients with bronchiolitis were randomly divided into two groups, 120 patients in the observation group on the basis of conventional therapy supplemented by joint Bricanyl Pulmicort inhalation of oxygen flooding; Control group, only routine treatment of 120 cases. Results The study group cough lost time, pulmonary auscultation and hospital stay were betler than that of the control group (P < 0. 05 ) , observation group the total effective rate was 91. 7% , that of the control group the total efficiency 55% , the difference between the two groups efficacy was statistically significant (P < 0. 05 ). Conclusions The combined Pulmicort and Bricanyl clinical treatment of children with bronchiolitis is effective, is worthy of clinical use.

  9. Evolution of Oxygenic Photosynthesis

    Science.gov (United States)

    Fischer, Woodward W.; Hemp, James; Johnson, Jena E.

    2016-06-01

    The origin of oxygenic photosynthesis was the most important metabolic innovation in Earth history. It allowed life to generate energy and reducing power directly from sunlight and water, freeing it from the limited resources of geochemically derived reductants. This greatly increased global primary productivity and restructured ecosystems. The release of O2 as an end product of water oxidation led to the rise of oxygen, which dramatically altered the redox state of Earth's atmosphere and oceans and permanently changed all major biogeochemical cycles. Furthermore, the biological availability of O2 allowed for the evolution of aerobic respiration and novel biosynthetic pathways, facilitating much of the richness we associate with modern biology, including complex multicellularity. Here we critically review and synthesize information from the geological and biological records for the origin and evolution of oxygenic photosynthesis. Data from both of these archives illustrate that this metabolism first appeared in early Paleoproterozoic time and, despite its biogeochemical prominence, is a relatively late invention in the context of our planet's history.

  10. Extra-corporeal membrane oxygenation

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007234.htm Extracorporeal membrane oxygenation To use the sharing features on this page, please enable JavaScript. Extracorporeal membrane oxygenation (ECMO) is a treatment that uses a ...

  11. LOG DURATION EMERGENCY OXYGEN BACKPACK.

    Science.gov (United States)

    A small backpack , for use by Naval aviators, containing a long duration emergency oxygen system and a separate humidifier for the aircraft’s oxygen supply, has been devised and a feasibility model built. (Author)

  12. Oxygen-Methane Thruster Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Orion Propulsion, Inc. proposes to develop an Oxygen and Methane RCS Thruster to advance the technology of alternate fuels. A successful Oxygen/CH4 RCS Thruster will...

  13. Aerosol Properties From Combined Oxygen A Band Radiances and Lidar

    Science.gov (United States)

    Winker, Dave; Zhai, Peng-Wang; Hu, Yongxiang

    2015-01-01

    We have developed a new aerosol retrieval technique based on combing high-resolution A band spectra with lidar profiles. Our goal is the development of a technique to retrieve aerosol absorption, one of the critical parameters affecting the global radiation budget and one which is currently poorly constrained by satellite measurements. Our approach relies on two key factors: 1) the use of high spectral resolution (17,000:1) measurements which resolve the A-band line structure, and 2) the use of co-located lidar profile measurements to constrain the vertical distribution of scatterers in the forward model. The algorithm has been developed to be applied to observations from the CALIPSO and OCO-2 satellites, flying in formation as part of the A-train constellation. We describe the approach and present simulated retrievals to illustrate performance potential.

  14. Oxygen Transport Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay

    2008-08-30

    The focus of this research was to develop new membrane materials by synthesizing different compounds and determining their defect structures, crystallographic structures and electrical properties. In addition to measuring electrical conductivity, oxygen vacancy concentration was also evaluated using thermogravimetry, Neutron diffraction and Moessbauer Spectroscopy. The reducing conditions (CO{sub 2}/CO/H{sub 2} gas mixtures with steam) as encountered in a reactor environment can be expected to have significant influence on the mechanical properties of the oxides membranes. Various La based materials with and without Ti were selected as candidate membrane materials for OTM. The maximum electrical conductivity of LSF in air as a function of temperature was achieved at < 600 C and depends on the concentration of Sr (acceptor dopant). Oxygen occupancy in LSF was estimated using Neutron diffractometry and Moessbauer Spectroscopy by measuring magnetic moment changes depending on the Fe{sup 3+} and Fe{sup 4+} ratio. After extensive studies of candidate materials, lanthanum ferrites (LSF and LSFT) were selected as the favored materials for the oxygen transport membrane (OTM). LSF is a very good material for an OTM because of its high electronic and oxygen ionic conductivity if long term stability and mechanical strength are improved. LSFT not only exhibits p-type behavior in the high oxygen activity regime, but also has n-type conduction in reducing atmospheres. Higher concentrations of oxygen vacancies in the low oxygen activity regime may improve the performance of LSFT as an OTM. The hole concentration is related to the difference in the acceptor and donor concentration by the relation p = [Sr'{sub La}]-[Ti{sm_bullet}{sub Fe}]. The chemical formulation predicts that the hole concentration is, p = 0.8-0.45 or 0.35. Experimental measurements indicated that p is about {approx} 0.35. The activation energy of conduction is 0.2 eV which implies that LSCF conducts via the

  15. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; N. Nagabhushana; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-02-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. Thermogravimetric analysis (TGA) was carried out on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} to investigate oxygen deficiency ({delta}) of the sample. The TGA was performed in a controlled atmosphere using oxygen, argon, carbon monoxide and carbon dioxide with adjustable gas flow rates. In this experiment, the weight loss and gain of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} was directly measured by TGA. The weight change of the sample was evaluated at between 600 and 1250 C in air or 1000 C as a function of oxygen partial pressure. The oxygen deficiencies calculated from TGA data as a function of oxygen activity and temperature will be estimated and compared with that from neutron diffraction measurement in air. The LSFT and LSFT/CGO membranes were fabricated from the powder obtained from Praxair Specialty Ceramics. The sintered membranes were subjected to microstructure analysis and hardness analysis. The LSFT membrane is composed of fine grains with two kinds of grain morphology. The grain size distribution was characterized using image analysis. In LSFT/CGO membrane a lot of grain pullout was observed from the less dense, porous phase. The hardness of the LSFT and dual phase membranes were studied at various loads. The hardness values obtained from the cross section of the membranes were also compared to that of the values obtained from the surface. An electrochemical cell has been designed and built for measurements of the Seebeck coefficient as a function of temperature and pressure. Measurements on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} as a function of temperature an oxygen partial pressure are reported. Further analysis of the dilatometry data obtained previously is presented. A series of isotope transients

  16. Experimental study on the treatment of bone nonunion of rabbit radius by extracorporeal shock wave com-bined with hyperbaric oxygen%体外冲击波联合高压氧治疗兔桡骨骨折骨不连的实验研究

    Institute of Scientific and Technical Information of China (English)

    郁少林; 李宏宇; 刘搏宇; 蔡敏; 杨勇; 来文兵

    2015-01-01

    目的:探讨体外冲击波联合高压氧治疗兔桡骨骨折骨不连的效果及作用原理。方法选用新西兰雄性健康标准实验大白兔48只(月龄及体重相当),无菌条件下制作兔双侧桡骨骨不连模型,采用随机数字表法随机分成四组,每组12只。其中A组为体外冲击波联合高压氧治疗组;B组为单纯高压氧治疗组;C组为单纯体外冲击波治疗组;D组为对照组,不做任何处理。分别在治疗前及治疗后第2、4、8、12周摄X线片并处死部分实验动物取活组织进行大体观察、骨折间隙变化、骨痂钙含量测定、光镜检查骨痂成骨细胞计数,最后进行统计学分析。结果 X线观察,A组与B、C、D组骨不连间隙4、8、12周差异有统计学意义( P<0.05)。 A、C两组骨痂钙元素含量2、4、8、12周差异有统计学意义( P<0.05),骨痂成骨细胞计数2、4、8周差异具有统计学意义( P<0.05)。结论体外冲击波联合高压氧对骨不连的治疗效果优于单纯体外冲击波治疗,单纯高压氧治疗对骨不连无明显帮助,高压氧可作为体外冲击波治疗骨不连的一种良好的协同方法。%Objective To explore the effect and action mechanism of extracorpoporeal shock wave combined with hyperbaric oxygen in the treatment of bone ununion .Methods Forty-eight health standard experiment New Zeal-and white rabbits were chosen ( months of age are consistent with weights ) , and divided into four groups by using the random number table after the models were made by osteotomy (12 in each group).The group A was extracorporeal shock wave combined with hyperbaric oxygen group; The group B was hyperbaric oxygen group; The group C was pure extracorporeal shock wave group;The group D was in control group , X-ray examination was made before treat-ment and at 2, 4, 8, 12 weeks after treatment;and part of the experimental animals were executed at each time point

  17. Mixed oxygen ion/electron-conducting ceramics for oxygen separation

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, J.W.; Armstrong, T.R.; Armstrong, B.L. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-08-01

    Mixed oxygen ion and electron-conducting ceramics are unique materials that can passively separate high purity oxygen from air. Oxygen ions move through a fully dense ceramic in response to an oxygen concentration gradient, charge-compensated by an electron flux in the opposite direction. Compositions in the system La{sub 1{minus}x}M{sub x}Co{sub 1{minus}y{minus}z}Fe{sub y}N{sub z}O{sub 3{minus}{delta}}, perovskites where M=Sr, Ca, and Ba, and N=Mn, Ni, Cu, Ti, and Al, have been prepared and their electrical, oxygen permeation, oxygen vacancy equilibria, and catalytic properties evaluated. Tubular forms, disks, and asymmetric membrane structures, a thin dense layer on a porous support of the same composition, have been fabricated for testing purposes. In an oxygen partial gradient, the passive oxygen flux through fully dense structures was highly dependent on composition. An increase in oxygen permeation with increased temperature is attributed to both enhanced oxygen vacancy mobility and higher vacancy populations. Highly acceptor-doped compositions resulted in oxygen ion mobilities more than an order of magnitude higher than yttria-stabilized zirconia. The mixed conducting ceramics have been utilized in a membrane reactor configuration to upgrade methane to ethane and ethylene. Conditions were established to balance selectivity and throughput in a catalytic membrane reactor constructed from mixed conducting ceramics.

  18. 氨溴特罗口服液联合复方异丙托溴铵氧气雾化吸入治疗小儿毛细支气管炎的临床价值%Clinical Value of Ambrocol Oral Liquid Combined With Ipratropium Bromide Oxygen Inhalation in the Treatment of Children With Bronchiolitis

    Institute of Scientific and Technical Information of China (English)

    杜燕

    2016-01-01

    Objective Analysis of Ambrocol oral liquid combined with ipratropium bromide oxygen inhalation in the treatment of children with bronchiolitis. Methods 78 cases of bronchiolitis in our hospital were divided into two groups,comparing the clinical effect. Results The total efficiency of the observation group was significantly better than the control group(P<0.05).Conclusion Children with bronchiolitis by ipratropium bromide and ambrocol oral solution for atomizing inhalation treatment can obtain the exact effect.%目的:探析小儿毛细支气管炎采用复方异丙托溴铵与氨溴特罗口服液给予雾化吸入治疗的效果。方法将我院收治的78例毛细支气管炎患儿分成两组,对比分析其临床效果。结果观察组治疗总有效率优于对照组(P<0.05)。结论小儿毛细支气管炎通过复方异丙托溴铵、氨溴特罗口服液联合给予雾化吸入治疗可获得确切的效果。

  19. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; T. Nithyanantham

    2006-12-31

    Ti doping on La{sub 1-x}Sr{sub x}FeO{sub 3-{delta}} (LSF) tends to increase the oxygen equilibration kinetics of LSF in lower oxygen activity environment because of the high valence state of Ti. However, the addition of Ti decreases the total conductivity because the acceptor ([Sr{prime}{sub La}]) is compensated by the donor ([Ti{sub Fe}{sup {sm_bullet}}]) which decreases the carrier concentration. The properties of La{sub 0.2}Sr{sub 0.8}Fe{sub 1-x}Ti{sub x}O{sub 3-{delta}} (LSFT, x = 0.45) have been experimentally and theoretically investigated to elucidate (1) the dependence of oxygen occupancy and electrochemical properties on temperature and oxygen activity by thermogravimetric analysis (TGA) and (2) the electrical conductivity and carrier concentration by Seebeck coefficient and electrical measurements. In the present study, dual phase (La{sub 0.2}Sr{sub 0.8}Fe{sub 0.6}Ti{sub 0.4}O{sub 3-{delta}}/Ce{sub 0.9}Gd{sub 0.1}O{sub 2-{delta}}) membranes have been evaluated for structural properties such as hardness, fracture toughness and flexural strength. The effect of high temperature and slightly reducing atmosphere on the structural properties of the membranes was studied. The flexural strength of the membrane decreases upon exposure to slightly reducing conditions at 1000 C. The as-received and post-fractured membranes were characterized using XRD, SEM and TG-DTA to understand the fracture mechanisms. Changes in structural properties of the composite were sought to be correlated with the physiochemical features of the two-phases. We have reviewed the electrical conductivity data and stoichiometry data for La{sub 0.2}Sr{sub 0.8}Cr{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} some of which was reported previously. Electrical conductivity data for La{sub 0.2}Sr{sub 0.8}Cr{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} (LSCrF) were obtained in the temperature range, 752 {approx} 1055 C and in the pO{sub 2} range, 10{sup -18} {approx} 0.5 atm. The slope of the plot of log {sigma} vs

  20. Oxygen transport and degradation processes in mixed conducting perovskites

    CERN Document Server

    Benson, S J

    2002-01-01

    surface exchange between the ceramic and oxygen ions in the carbon dioxide and water has been investigated using sup 1 sup 8 O isotopically labelled species combined with SIMS. Also presented in Part 2 is an overview of the principles involved in the application of MIEC ceramics in oxygen separation membranes, with respect to the optimisation of oxygen fluxes and membrane performance. The application of oxide ion conducting ceramics in solid oxide electrochemical devices, such as solid oxide fuel cells, air separation membranes and oxygen sensors, is an area currently of great commercial interest. Much recent research has focused on the optimisation of the structural and electrical properties of these ceramics. However little is known about the long term stability of these materials under the realistic operating conditions of the systems, and it is this concern which has provided the motivation for this project. The study has been divided into two sections. Part 1 deals with the measurement of the oxygen tran...

  1. Direct measurement of oxygen stoichiometry in perovskite films

    Science.gov (United States)

    Scola, J.; Benamar, A.; Berini, B.; Jomard, F.; Dumont, Y.

    2017-02-01

    We present a direct method to measure the oxygen stoichiometry in an oxide film with an accuracy of about 2%. It is based on a combination of 18O annealing and high mass resolution secondary ion mass spectroscopy. Calibration has been done on a LaNiO3 film whose electrical properties dependence on oxygen stoichiometry are well documented. The method is illustrated with a series of LaNiO3 films grown on SrTiO3 substrates prepared with different oxygen stoichiometries. The large influence of the surface state on oxygen exchange is evidenced in films grown on different substrate orientations or coated with a thin layer of LaAlO3. Oxygen surface exchange and bulk diffusion is then discussed for both LaNiO3 and SrVO3 films.

  2. Oxygen Reduction on Platinum

    DEFF Research Database (Denmark)

    Nesselberger, Markus

    This thesis investigates the electro reduction of oxygen on platinum nanoparticles, which serve as catalyst in low temperature fuel cells. Kinetic studies on model catalysts as well as commercially used systems are presented in order to investigate the particle size effect, the particle proximity...... carbon (HSAC) supported Pt nanoparticle (Pt/C) catalysts (of various size between 1 and 5 nm). The difference in SA between the individual Pt/C catalysts (1 to 5 nm) is very small and within the error of the measurements. The factor four of loss in SA when comparing platinum bulk and Pt/C can largely...

  3. Oxygen Isotopes in Meteorites

    Science.gov (United States)

    Clayton, R. N.

    2003-12-01

    Oxygen isotope abundance variations in meteorites are very useful in elucidating chemical and physical processes that occurred during the formation of the solar system (Clayton, 1993). On Earth, the mean abundances of the three stable isotopes are 16O: 99.76%, 17O: 0.039%, and 18O: 0.202%. It is conventional to express variations in abundances of the isotopes in terms of isotopic ratios, relative to an arbitrary standard, called SMOW (for standard mean ocean water), as follows:The isotopic composition of any sample can then be represented by one point on a "three-isotope plot," a graph of δ17O versus δ18O. It will be seen that such plots are invaluable in interpreting meteoritic data. Figure 1 shows schematically the effect of various processes on an initial composition at the center of the diagram. Almost all terrestrial materials lie along a "fractionation" trend; most meteoritic materials lie near a line of "16O addition" (or subtraction). (4K)Figure 1. Schematic representation of various isotopic processes shown on an oxygen three-isotope plot. Almost all terrestrial materials plot along a line of "fractionation"; most primitive meteoritic materials plot near a line of "16O addition." The three isotopes of oxygen are produced by nucleosynthesis in stars, but by different nuclear processes in different stellar environments. The principal isotope, 16O, is a primary isotope (capable of being produced from hydrogen and helium alone), formed in massive stars (>10 solar masses), and ejected by supernova explosions. The two rare isotopes are secondary nuclei (produced in stars from nuclei formed in an earlier generation of stars), with 17O coming primarily from low- and intermediate-mass stars (shielding in the UV photodissociation of CO (van Dishoeck and Black, 1988). This process results from the large differences in abundance between C16O, on the one hand, and C17O and C18O on the other. Photolysis of CO occurs by absorption of stellar UV radiation in the

  4. Timescales of Oxygenation Following the Evolution of Oxygenic Photosynthesis.

    Science.gov (United States)

    Ward, Lewis M; Kirschvink, Joseph L; Fischer, Woodward W

    2016-03-01

    Among the most important bioenergetic innovations in the history of life was the invention of oxygenic photosynthesis-autotrophic growth by splitting water with sunlight-by Cyanobacteria. It is widely accepted that the invention of oxygenic photosynthesis ultimately resulted in the rise of oxygen by ca. 2.35 Gya, but it is debated whether this occurred more or less immediately as a proximal result of the evolution of oxygenic Cyanobacteria or whether they originated several hundred million to more than one billion years earlier in Earth history. The latter hypothesis involves a prolonged period during which oxygen production rates were insufficient to oxidize the atmosphere, potentially due to redox buffering by reduced species such as higher concentrations of ferrous iron in seawater. To examine the characteristic timescales for environmental oxygenation following the evolution of oxygenic photosynthesis, we applied a simple mathematical approach that captures many of the salient features of the major biogeochemical fluxes and reservoirs present in Archean and early Paleoproterozoic surface environments. Calculations illustrate that oxygenation would have overwhelmed redox buffers within ~100 kyr following the emergence of oxygenic photosynthesis, a geologically short amount of time unless rates of primary production were far lower than commonly expected. Fundamentally, this result arises because of the multiscale nature of the carbon and oxygen cycles: rates of gross primary production are orders of magnitude too fast for oxygen to be masked by Earth's geological buffers, and can only be effectively matched by respiration at non-negligible O2 concentrations. These results suggest that oxygenic photosynthesis arose shortly before the rise of oxygen, not hundreds of millions of years before it.

  5. Drugs (including oxygen) in severe COPD.

    Science.gov (United States)

    Albert, P; Calverley, P M A

    2008-05-01

    Access to comprehensive guidelines on the management of chronic obstructive pulmonary disease (COPD) is now available, and several treatment goals of therapy have been identified from these guidelines, which have since been studied in clinical trials. Drug therapy is a key component of an individual patient's management plan, particularly in more severe disease. During the past few years, a number of new drug treatments have become available, although these are not always appropriately prescribed; this is particularly the case for oxygen. For patients with a history of exacerbations, there is good evidence for the use of inhaled long-acting anticholinergic agents or combined inhaled steroids and long-acting beta-agonists. Evidence for prophylactic antibiotics and antioxidant agents is lacking. Nutritional and calorie supplementation have not been shown to improve exercise capacity. Statins may improve outcomes in COPD, but prospective trials are needed to confirm this. The evidence for the use of long-term oxygen therapy in hypoxaemic patients is robust. Ambulatory oxygen improves exercise capacity, but whether it is used appropriately is in doubt. Overall, short burst oxygen therapy does not offer a benefit and therefore cannot be recommended.

  6. Mechanism of oxygen releasing of copper ferrite in the formation of the corresponding oxygen-deficient compound

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ping; YU Bo; ZHANG Lei

    2009-01-01

    Copper ferrite is a promising material for hydrogen production through thermochemical water splitting. In this work, the cation distribution of copper ferrite and the corresponding oxygen-deficient compound of spinel structure was analyzed based on the crystal structural chemistry theory. The mechanism of oxygen releasing of CuO, Fe2O3, CuFe2O4 and metal (M=Ni, Mn or Zn) doped copper ferrite in the proc-ess of temperature rising was investigated by differential thermal analysis-thermogravimetry (DTA-TG). By combining the theoretical analysis with experimental results, the mechanism of oxygen releasing of copper ferrite is proposed, which is different from that of other ferrites. For copper ferrite, the oxygen releasing caused by Cu(Ⅱ)→Cu(I) plays a predominant role, while for other ferrites, the oxygen releas-ing resulting from Fe(ⅡI)→Fe(Ⅱ) is dominant.

  7. Mechanism of oxygen releasing of copper ferrite in the formation of the corresponding oxygen-deficient compound

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Copper ferrite is a promising material for hydrogen production through thermochemical water splitting.In this work,the cation distribution of copper ferrite and the corresponding oxygen-deficient compound of spinel structure was analyzed based on the crystal structural chemistry theory.The mechanism of oxygen releasing of CuO,Fe2O3,CuFe2O4 and metal(M=Ni,Mn or Zn) doped copper ferrite in the proc-ess of temperature rising was investigated by differential thermal analysis-thermogravimetry(DTA-TG).By combining the theoretical analysis with experimental results,the mechanism of oxygen releasing of copper ferrite is proposed,which is different from that of other ferrites.For copper ferrite,the oxygen releasing caused by Cu(Ⅱ)→Cu(Ⅰ) plays a predominant role,while for other ferrites,the oxygen releas-ing resulting from Fe(Ⅲ)→Fe(Ⅱ) is dominant.

  8. OXYGEN TRANSPORT CERAMIC MEMBRANES

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2000-10-01

    This is the third quarterly report on oxygen Transport Ceramic Membranes. In the following, the report describes the progress made by our university partners in Tasks 1 through 6, experimental apparatus that was designed and built for various tasks of this project, thermodynamic calculations, where applicable and work planned for the future. (Task 1) Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. (Task 2) Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. (Task 3) Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. (Task 4) Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. (Task 5) Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. (Task 6) Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

  9. Composite oxygen transport membrane

    Science.gov (United States)

    Christie, Gervase Maxwell; Lane, Jonathan A.

    2014-08-05

    A method of producing a composite oxygen ion membrane and a composite oxygen ion membrane in which a porous fuel oxidation layer and a dense separation layer and optionally, a porous surface exchange layer are formed on a porous support from mixtures of (Ln.sub.1-xA.sub.x).sub.wCr.sub.1-yB.sub.yO.sub.3-.delta. and a doped zirconia. In the porous fuel oxidation layer and the optional porous surface exchange layer, A is Calcium and in the dense separation layer A is not Calcium and, preferably is Strontium. Preferred materials are (La.sub.0.8Ca.sub.0.2).sub.0.95Cr.sub.0.5Mn.sub.0.5O.sub.3-.delta. for the porous fuel oxidation and optional porous surface exchange layers and (La.sub.0.8Sr.sub.0.2).sub.0.95Cr.sub.0.5Fe.sub.0.5O.sub.3-.delta. for the dense separation layer. The use of such materials allows the membrane to sintered in air and without the use of pore formers to reduce membrane manufacturing costs. The use of materials, as described herein, for forming the porous layers have application for forming any type of porous structure, such as a catalyst support.

  10. Oxygen-Methane Thruster

    Science.gov (United States)

    Pickens, Tim

    2012-01-01

    An oxygen-methane thruster was conceived with integrated igniter/injector capable of nominal operation on either gaseous or liquid propellants. The thruster was designed to develop 100 lbf (approximately 445 N) thrust at vacuum conditions and use oxygen and methane as propellants. This continued development included refining the design of the thruster to minimize part count and manufacturing difficulties/cost, refining the modeling tools and capabilities that support system design and analysis, demonstrating the performance of the igniter and full thruster assembly with both gaseous and liquid propellants, and acquiring data from this testing in order to verify the design and operational parameters of the thruster. Thruster testing was conducted with gaseous propellants used for the igniter and thruster. The thruster was demonstrated to work with all types of propellant conditions, and provided the desired performance. Both the thruster and igniter were tested, as well as gaseous propellants, and found to provide the desired performance using the various propellant conditions. The engine also served as an injector testbed for MSFC-designed refractory combustion chambers made of rhenium.

  11. OXYGEN ABUNDANCES IN CEPHEIDS

    Energy Technology Data Exchange (ETDEWEB)

    Luck, R. E.; Andrievsky, S. M. [Department of Astronomy, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-7215 (United States); Korotin, S. N.; Kovtyukh, V. V., E-mail: luck@fafnir.astr.cwru.edu, E-mail: serkor@skyline.od.ua, E-mail: val@deneb1.odessa.ua, E-mail: scan@deneb1.odessa.ua [Department of Astronomy and Astronomical Observatory, Odessa National University, Isaac Newton Institute of Chile, Odessa Branch, Shevchenko Park, 65014 Odessa (Ukraine)

    2013-07-01

    Oxygen abundances in later-type stars, and intermediate-mass stars in particular, are usually determined from the [O I] line at 630.0 nm, and to a lesser extent, from the O I triplet at 615.7 nm. The near-IR triplets at 777.4 nm and 844.6 nm are strong in these stars and generally do not suffer from severe blending with other species. However, these latter two triplets suffer from strong non-local thermodynamic equilibrium (NLTE) effects and thus see limited use in abundance analyses. In this paper, we derive oxygen abundances in a large sample of Cepheids using the near-IR triplets from an NLTE analysis, and compare those abundances to values derived from a local thermodynamic equilibrium (LTE) analysis of the [O I] 630.0 nm line and the O I 615.7 nm triplet as well as LTE abundances for the 777.4 nm triplet. All of these lines suffer from line strength problems making them sensitive to either measurement complications (weak lines) or to line saturation difficulties (strong lines). Upon this realization, the LTE results for the [O I] lines and the O I 615.7 nm triplet are in adequate agreement with the abundance from the NLTE analysis of the near-IR triplets.

  12. Cerebral oxygenation and hyperthermia

    Directory of Open Access Journals (Sweden)

    Anthony Richard Bain

    2014-03-01

    Full Text Available Hyperthermia is associated with marked reductions in cerebral blood flow (CBF. Increased distribution of cardiac output to the periphery, increases in alveolar ventilation and resultant hypocapnia each contribute to the fall in CBF during passive hyperthermia; however, their relative contribution remains a point of contention, and probably depends on the experimental condition (e.g. posture and degree of hyperthermia. The hyperthermia-induced hyperventilatory response reduces arterial CO2 pressure (PaCO2 causing cerebral vasoconstriction and subsequent reductions in flow. During supine passive hyperthermia, the majority of recent data indicate that reductions in PaCO2 may be the primary, if not sole, culprit for reduced CBF. On the other hand, during more dynamic conditions (e.g. hemorrhage or orthostatic challenges, an inability to appropriately decrease peripheral vascular conductance presents a condition whereby adequate cerebral perfusion pressure may be compromised secondary to reductions in systemic blood pressure. Although studies have reported maintenance of pre-frontal cortex oxygenation (assessed by near-infrared spectroscopy during exercise and severe heat stress, the influence of cutaneous blood flow is known to contaminate this measure. This review discusses the governing mechanisms associated with changes in CBF and oxygenation during moderate to severe (i.e. 1.0°C to 2.0°C increase in body core temperature levels of hyperthermia. Future research directions are provided.

  13. Composite oxygen transport membrane

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Zigui; Plonczak, Pawel J.; Lane, Jonathan A.

    2016-11-08

    A method is described of producing a composite oxygen ion membrane and a composite oxygen ion membrane in which a porous fuel oxidation layer and a dense separation layer and optionally, a porous surface exchange layer are formed on a porous support from mixtures of (Ln.sub.1-xA.sub.x).sub.wCr.sub.1-yB.sub.yO.sub.3-.delta. and a doped zirconia. Preferred materials are (La.sub.0.8Sr.sub.0.2).sub.0.95Cr.sub.0.7Fe.sub.0.3O.sub.3-.delta. for the porous fuel oxidation layer, (La.sub.0.8Sr.sub.0.2).sub.0.95Cr.sub.0.5Fe.sub.0.5O.sub.3-.delta. for the dense separation layer, and (La.sub.0.8Sr.sub.0.2).sub.0.95Cr.sub.0.3Fe.sub.0.7O.sub.3-.delta. for the porous surface exchange layer. Firing the said fuel activation and separation layers in nitrogen atmosphere unexpectedly allows the separation layer to sinter into a fully densified mass.

  14. Composite oxygen transport membrane

    Energy Technology Data Exchange (ETDEWEB)

    Christie, Gervase Maxwell; Lane, Jonathan A.

    2016-11-15

    A method of producing a composite oxygen ion membrane and a composite oxygen ion membrane in which a porous fuel oxidation layer and a dense separation layer and optionally, a porous surface exchange layer are formed on a porous support from mixtures of (Ln.sub.1-xA.sub.x).sub.wCr.sub.1-yB.sub.yO.sub.3-.delta. and a doped zirconia. In the porous fuel oxidation layer and the optional porous surface exchange layer, A is Calcium and in the dense separation layer A is not Calcium and, preferably is Strontium. Preferred materials are (La.sub.0.8Ca.sub.0.2).sub.0.95Cr.sub.0.5Mn.sub.0.5O.sub.3-.delta. for the porous fuel oxidation and optional porous surface exchange layers and (La.sub.0.8Sr.sub.0.2).sub.0.95Cr.sub.0.5Fe.sub.0.5O.sub.3-.delta. for the dense separation layer. The use of such materials allows the membrane to sintered in air and without the use of pore formers to reduce membrane manufacturing costs. The use of materials, as described herein, for forming the porous layers have application for forming any type of porous structure, such as a catalyst support.

  15. Analysis of therapeutic effect of hyperbaric oxygen therapy on neuropsychological disorders in senile patients with type 2 diabetes mellitus combined with cerebral infarction%高压氧治疗老年2型糖尿病并存脑梗死患者神经心理障碍的疗效分析

    Institute of Scientific and Technical Information of China (English)

    陈灶萍; 刘军; 查英; 盛励; 史莉华

    2008-01-01

    Objective To explore the therapeutic effect of hyperbaric oxygen therapy (HBO) in the treatment of neuropsychological disorders in senile patients with type 2 diabetes mellitus combined with cerebral infarction. Methods A total of 70 senile patients with type 2 diabetes mellitus combined with cerebral infarction were randomly divided into two groups: treatment group receiving HBO plus routine medicine treatment and control group receiving routing medicine treatment only. A suit of senile neuropsychological tests was administered pre and post treatment by an experienced psychometrician who was blinded to treatment group assignments. Results Neuropsychological disorders were improved partly in control group while the efficacy in treatment group was markedly improved(P<0.01). Spearman rank correlation analysis revealed that the improvement degree of neuropsychological disorders was positively correlated with hyperbaric oxygen therapy (HBO) (r= 0.502,P<0.05), the time of test before therapy (r=0.260, P<0.05) and the time of test after therapy (r=0.386, P<0.05), and was negatively correlated with hyperlipoidemia (r=-0.261, P< 0.05), glycosylated hemoglobin(GHbAlc) (r=-0.321,P<0.05) and body mass index(BMI) (r= 0.360,P<0.05). Multiple stepwise regression analysis showed that HBO and hyperlipoidemia were the independent predictors for the improvement degree of neuropsychological disorders. Conclusions HBO is an efficacious way to treat neuropsychological disorders in senile patients with type 2 diabetes mellitus combined with cerebral infarction.%目的 探讨高压氧治疗老年2型糖尿病并存脑梗死患者神经心理障碍的有效性. 方法 将70例入选患者随机分为治疗组和对照组,治疗组在常规药物治疗基础上联合10次高压氧治疗.选用老年成套心理测验,对所有患者治疗前后进行测试. 结果 对照组患者神经心理障碍得到部分改善,治疗组患者改善程度明显提高(P<0.01).Spearman相关分析显示

  16. Observation on the Therapeutic Effect of Budesonide Inhalation Via Oxygen-Driven Atomization Combined with Tanreqing Injection in Treatment of 100 Children Capillarity Bronchitis%布地奈德联合痰热清治疗婴幼儿毛细支气管炎疗效观察

    Institute of Scientific and Technical Information of China (English)

    吴晓秋; 沈琪; 杨彤; 黄献文

    2013-01-01

    目的观察布地奈德雾化雾化吸入联合痰热清静脉滴注治疗婴幼儿毛细支气管炎的临床疗效。方法将100例婴幼儿毛细支气管炎患儿随机分为治疗组和对照组各50例,两组均采用吸氧、镇静、解痉平喘、纠正水及电解质平衡紊乱等常规治疗。在常规治疗基础上,治疗组给予布地奈德混悬液(普米克令舒,lmg/2mL)1mL氧气驱动雾化,2次/日,5-7d为1疗程;痰热清注射液0.3-0.5mL/kg,最大剂量10mL,加入5%GS或0.9%NS100-200mL静脉滴注,控制滴速20-30滴/分,1次/日,3-5d为1疗程。对照组给予头孢他啶50-100mg/(kg· d)、利巴韦林10-15mg/(kg· d)分别加入5%GS100-150 mL静脉滴注,1次/日,治疗5-7 d。观察并比较两组总有效率和咳喘、哮鸣音、湿啰音消失时间及住院时间等。结果治疗组总有效率96.0%,高于对照组的74.0%(P<0.05);治疗组咳喘、哮鸣音、湿啰音消失时间及住院时间均短于对照组(P均<0.05);两组均未发现明显不良反应。结论布地奈德雾化吸入联合痰热清静脉滴注对婴幼儿毛细支气管炎疗效良好,可明显改善其临床症状,值得临床推广应用。%Objective To investigate the therapeutic effect of Budesonide inhalation via oxygen -driven atomization combined with Tanreqing injection in treatment of 100 children capillarity bronchitis.Methods 100 children patients with capillarity bronchitis were randomly divided into a treatment group (n=50)and a control group (n=50).All children patients were given with oxygen,sedative,asthma and symptomatic treatment,the treatment group received extra treatment with budesonide inhala-tion via oxygen-driven atomization combined with Tanreqing injection treatment ,the control group received extra treatment with ribavirin and ceftazidime for injection treatment.Comparative analysis of total effective rate,disappearance time of cough

  17. 高压氧联合甲钴胺治疗腕管综合征的神经电生理疗效观察%Observation on the effects of hypesbaric oxygen combined with mecobalamin on electrophysiological changes in the treatment of carpal tunnel syndrome

    Institute of Scientific and Technical Information of China (English)

    朱连海; 丁莉; 李新玲; 陆珍辉; 凌卓敏

    2016-01-01

    目的 探讨高压氧联合甲钴胺治疗腕管综合征(CTS)的神经电生理疗效.方法 经患者知情同意,并签署知情同意书,将84例CTS患者分成甲钴胺组28例、高压氧组26例和高压氧联合甲钴胺组28例,甲钴胺组予甲钴胺治疗,高压氧组予高压氧治疗,高压氧联合甲钴胺组予甲钴胺及高压氧协同治疗,治疗前后均行电生理检查.结果 治疗后,高压氧联合甲钴胺组正中神经感觉神经传导速度(SCV)、运动神经传导速度(MCV)及运动神经复合肌动作电位(CMAP)波幅均高于治疗前(P<0.05),CMAP潜伏期(BML)低于治疗前(P<0.05);甲钴胺组治疗后[(30.22 ±3.18) m/s]正中神经SCV高于治疗前[(29.54±2.61) m/s](P<0.05);高压氧组治疗后正中神经SCV、MCV高于治疗前(P<0.05);高压氧组、高压氧联合甲钴胺组正中神经SCV、CMAP波幅较甲钴胺组明显提高(P<0.05);高压氧联合甲钴胺组正中神经SCV较高压氧组明显提高(P<0.05).结论 高压氧联合甲钴胺治疗CTS效果显著.%Objective To investigate the effects of hyperbaric oxygen (HBO) combined with mecobalamin on electrophysiological changes in the treatment of carpal tunnel syndrome (CTS).Methods Eighty-four cases of CTS were randomly divided into the mecobalamin group (n =28),the HBO group (n =28) and the HBO + mecobalamin group (n =28).The mecobalamin group was treated with mecobalamin,the HBO group received HBO therapy,and the latter group was given combined therapy,i.e.HBO plus mecobalamin.Both before and after treatment,all the patients received electrophysiological detection.Results After treatment,the median nerve sensory nerve conduction velocity (SCV),motor nerve conduction velocity (MCV),and the wave amplitude of the motor nerve compound muscle action potential (CMAP) of the combined group were all higher than those before treatment (P < 0.05),while CMAP latency (BML) was lower than that before treatment (P < 0.05).Following treatment,SCV of

  18. Fires and Burns Involving Home Medical Oxygen

    Science.gov (United States)

    ... nfpa.org Fires and Burns Involving Home Medical Oxygen The air is normally 21% oxygen. Oxygen is not flammable, but fire needs it to burn. ¾ When more oxygen is present, any fire that starts will burn ...

  19. The natural history of oxygen.

    Science.gov (United States)

    Dole, M

    1965-09-01

    The nuclear reactions occurring in the cores of stars which are believed to produce the element oxygen are first described. Evidence for the absence of free oxygen in the early atmosphere of the earth is reviewed. Mechanisms of creation of atmospheric oxygen by photochemical processes are then discussed in detail. Uncertainty regarding the rate of diffusion of water vapor through the cold trap at 70 km altitude in calculating the rate of the photochemical production of oxygen is avoided by using data for the concentration of hydrogen atoms at 90 km obtained from the Meinel OH absorption bands. It is estimated that the present atmospheric oxygen content could have been produced five to ten times during the earth's history. It is shown that the isotopic composition of atmospheric oxygen is not that of photosynthetic oxygen. The fractionation of oxygen isotopes by organic respiration and oxidation occurs in a direction to enhance the O(18) content of the atmosphere and compensates for the O(18) dilution resulting from photosynthetic oxygen. Thus, an oxygen isotope cycle exists in nature.

  20. 一氧化碳中毒迟发脑病患者高压氧综合治疗前后脑葡萄糖代谢的变化%Change of cerebral metabolism rate of glucose in patient of delayed neuropsychologlcal sequelae after CO poisoning following combining hyperbaric oxygen treatment

    Institute of Scientific and Technical Information of China (English)

    高宇; 高春锦; 王铁; 葛环; 武连华; 赵立明; 宋振国

    2008-01-01

    Objective To estimate the effect of hyperbaric oxygen treatment on cerebral metabolism rate of glucose(CMRglc)in patients with delayed neuropsychological sequelae after CO poisoning(DNS).Methods Thirty cases of DNS were received 18F-FDGPET examination before hyperbaric oxygen treatment (HBOT)and after 40th HBOT respectively.At the same time 17 healthy examiner were also received 18F-FDG PET examination.Radioactive counts in bilateral frontal lobe,parietal lobe,temporal lobe,occipital lobe and ipsilateral cerebellum unit area were recorded,and the radio of radioactive counts were measured and used to evaluate PET study as semi-quantitative parameter.Results The CMRglc of DNS patient decreased in bilateral frontal lobe,parietal lobe,temporal lobe and occipital lobe before HBOT(P<0.05).After HBOT,there were obvious improvement of CMRglc in bilateral parietal lobe,occipital lobe and left side temporal lobe(P<0.05)and no differences in bilateral frontal lobe and right side temporal lobe.Conclusions The CMRglc decreased on the early phase of DNS.Combining hyperbaric oxygen treatment can improve CMRglc and cerebral function.%目的 观察一氧化碳中毒迟发脑病高压氧综合治疗前后患者脑葡萄糖代谢的变化,探讨高压氧综合治疗的作用.方法 一氧化碳中毒迟发脑病(DNS)患者30例(DNS组),高压氧综合治疗前及治疗40次后分别接受18F标记的脱氧葡萄糖正电子发射断层扫描(18F-FDG PET)检查,同时对17例年龄匹配的健康体检者(对照组)进行18F-FDG PET检查.记录DNS组与对照组的双侧额叶、顶叶、颞叶、枕叶与同侧小脑单位面积的放射性计数;计算双侧额叶、顶叶、颞叶、枕叶与同侧小脑单位面积放射性计数的比值,以此比值作为PET研究的半定量观察指标.结果 DNS组高压氧综合治疗前双侧的额/小脑、顶/小脑、颞/小脑、枕/1h脑的比值明显低于对照组(P<0.05);高压氧综合治疗40次后,双侧的顶/小脑、

  1. Which blood oxygen can sensitively indicate shock severity?

    Science.gov (United States)

    Pan, Boan; Li, Kai; Gao, Yuan; Ruan, Zhengshang; Li, Ting

    2016-03-01

    Clinical shock-monitoring mainly depends on measuring oxygen saturations from SVC blood samples invasively. The golden standard indicator is the central internal jugular vein oxygenation (SjvO2). Using near-infrared spectroscopy (NIRS) also can monitor shock in some papers published, but there is no discussion about which oxygen saturation (cerebral venous oxygen saturation, ScvO2; tissue oxygen saturation of internal jugular area; tissue oxygen saturation of extremities areas) can monitor shock patient more sensitively and accurately. The purpose of this paper is to examine which one is most effective. In order to discuss the problem, we continuously detected 56 critical patients who may be into shock state using NIRS oximeter at prefrontal, internal jugular vein area and forearm, and chose 24 patients who were into shock and then out of shock from the 56 critical patients. Combined with the patients' condition, the pulse oxygen saturation is most sensitively to monitoring shock than the others, and the internal jugular vein area oxygen saturation is most effective.

  2. Fluorescence lifetime imaging of oxygen in dental biofilm

    Science.gov (United States)

    Gerritsen, Hans C.; de Grauw, Cees J.

    2000-12-01

    Dental biofilm consists of micro-colonies of bacteria embedded in a matrix of polysaccharides and salivary proteins. pH and oxygen concentration are of great importance in dental biofilm. Both can be measured using fluorescence techniques. The imaging of dental biofilm is complicated by the thickness of the biofilms that can be up to several hundred micrometers thick. Here, we employed a combination of two-photon excitation microscopy with fluorescence lifetime imaging to quantify the oxygen concentration in dental biofilm. Collisional quenching of fluorescent probes by molecular oxygen leads to a reduction of the fluorescence lifetime of the probe. We employed this mechanism to measure the oxygen concentration distribution in dental biofilm by means of fluorescence lifetime imaging. Here, TRIS Ruthenium chloride hydrate was used as an oxygen probe. A calibration procedure on buffers was use to measure the lifetime response of this Ruthenium probe. The results are in agreement with the Stern-Volmer equation. A linear relation was found between the ratio of the unquenched and the quenched lifetime and the oxygen concentration. The biofilm fluorescence lifetime imaging results show a strong oxygen gradient at the buffer - biofilm interface and the average oxygen concentration in the biofilm amounted to 50 μM.

  3. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; Q. Cai; J. Yang; W.B. Yelon; W.J. James; H.U. Anderson; Alan Jacobson; C.A. Mims

    2004-05-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In this report, in situ neutron diffraction was used to characterize the chemical and structural properties of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} (here after as L2SF55T) specimen, which was subject to measurements of neutron diffraction from room temperature to 900 C. It was found that space group of R3c yielded a better refinement than a cubic structure of Pm3m. Oxygen occupancy was nearly 3 in the region from room temperature to 700 C, above which the occupancy decreased due to oxygen loss. Dense OTM bars provided by Praxair were loaded to fracture at varying stress rates. Studies were done at room temperature in air and at 1000 C in a specified environment to evaluate slow crack growth behavior. The X-Ray data and fracture mechanisms points to non-equilibrium decomposition of the LSFCO OTM membrane. The non-equilibrium conditions could probably be due to the nature of the applied stress field (stressing rates) and leads to transition in crystal structures and increased kinetics of decomposition. The formations of a Brownmillerite or Sr2Fe2O5 type structures, which are orthorhombic are attributed to the ordering of oxygen vacancies. The cubic to orthorhombic transitions leads to 2.6% increase in strains and thus residual stresses generated could influence the fracture behavior of the OTM membrane. Continued investigations on the thermodynamic properties (stability and phase-separation behavior) and total conductivity of prototype membrane materials were carried out. The data are needed together with the kinetic information to develop a complete model for the membrane transport. Previously characterization, stoichiometry and conductivity measurements for samples of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} were reported. In this report

  4. A Small Oxygen Concentrator

    Science.gov (United States)

    1985-12-01

    150- S40- 20- 10 0 0 10 i0 30 40 NUIT PRESS=R (psig Figure 7. Percentage of oxygen. versus inlet pressure when using Soc with 131 molecular s ieve. 70...chick valve ano *move the plunger and spring. Disca the plunger; the spring will W• reused. Mill a SS sleeve to 0.535" 0.0. and 0.50" I.D. and press tit...the fjur 1" caps. The i n- side of two of the caps is milled flat to a diameteýr of 7/8". P-Kace one ena of a 10’, length of 1/2" SS tube in each Of

  5. Optic nerve oxygenation

    DEFF Research Database (Denmark)

    Stefánsson, Einar; Pedersen, Daniella Bach; Jensen, Peter Koch;

    2005-01-01

    -oxygenase inhibitor, indomethacin, which indicates that prostaglandin metabolism plays a role. Laboratory studies suggest that carbonic anhydrase inhibitors might be useful for medical treatment of optic nerve and retinal ischemia, potentially in diseases such as glaucoma and diabetic retinopathy. However, clinical...... at similar levels of perfusion pressure. The levels of perfusion pressure that lead to optic nerve hypoxia in the laboratory correspond remarkably well to the levels that increase the risk of glaucomatous optic nerve atrophy in human glaucoma patients. The risk for progressive optic nerve atrophy in human...... glaucoma patients is six times higher at a perfusion pressure of 30 mmHg, which corresponds to a level where the optic nerve is hypoxic in experimental animals, as compared to perfusion pressure levels above 50 mmHg where the optic nerve is normoxic. Medical intervention can affect optic nerve oxygen...

  6. Optic nerve oxygenation

    DEFF Research Database (Denmark)

    Stefánsson, Einar; Pedersen, Daniella Bach; Jensen, Peter Koch;

    2005-01-01

    at similar levels of perfusion pressure. The levels of perfusion pressure that lead to optic nerve hypoxia in the laboratory correspond remarkably well to the levels that increase the risk of glaucomatous optic nerve atrophy in human glaucoma patients. The risk for progressive optic nerve atrophy in human...... glaucoma patients is six times higher at a perfusion pressure of 30 mmHg, which corresponds to a level where the optic nerve is hypoxic in experimental animals, as compared to perfusion pressure levels above 50 mmHg where the optic nerve is normoxic. Medical intervention can affect optic nerve oxygen......-oxygenase inhibitor, indomethacin, which indicates that prostaglandin metabolism plays a role. Laboratory studies suggest that carbonic anhydrase inhibitors might be useful for medical treatment of optic nerve and retinal ischemia, potentially in diseases such as glaucoma and diabetic retinopathy. However, clinical...

  7. Intraoperative blood oxygenation continuous pulmonary artery perfusion lung protection of ventricular septal defect combined children with pulmonary hypertension%术中氧合血持续肺动脉灌注对室间隔缺损合并肺动脉高压患儿的肺保护作用

    Institute of Scientific and Technical Information of China (English)

    章晔; 李春玲; 胡建明; 林庆; 陈艰

    2014-01-01

    目的:研究在体外循环手术中使用氧合血进行持续肺动脉灌注对合并肺动脉高压的室间隔缺损患儿的肺保护作用。方法30例室间隔缺损合并肺动脉高压的患儿,随机均分为试验组和对照组。均在体外循环下进行室间隔缺损修补手术。试验组在体外循环中采用氧合血持续肺动脉灌注,对照组未行肺动脉灌注。两组患儿在体外循环前,主动脉开放后6、12、24h时抽取动脉血3ml.采用酶联免疫吸附法(ELISA法)检测丙二醛(MDA)的水平。并抽取动脉血进行血气分析,计算体外循环前,主动脉开放后6、12、24h时的氧合指数(QI),并记录气道峰压和呼吸机辅助时间,进行统计分析。结果试验组术后12、24h的 QI高于对照组(P<0.05),试验组术后6、12h的气道峰压明显低于对照组(P<0.05)。试验组术后呼吸机辅助时间明显低于对照组(P<0.05)。试验组术后6、12、24h时MDA水平均低于对照组(P<0.05)。结论氧合血持续肺动脉灌注能减轻室间隔缺损合并肺动脉高压患儿在体外循环中的肺损伤。%Objective To study the effects of blood oxygenation in extracorporeal circulation operation on continuous pul-monary artery perfusion of merger pulmonary hypertension of ventricular septal defect with pulmonary protection. Methods 30 cases of ventricular septal defect combined pulmonary hypertension were randomly divided into experimental group and control group,15 cases in each group. Both ventricular septal defect repair surgery under extracorporeal circulation. Patients with blood oxygenation in extracorporeal circulation continuous pulmonary artery perfusion, the control group no pulmonary artery perfusion. Two groups of children in front of the extracorporeal circulation, aorta open after 6,12 and 24 h when extracting arterial blood 3 ml. By using enzyme-linked immunosorbent (ELISA) to detect malondialdehyde (MDA

  8. Oxygen-reducing catalyst layer

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Dennis P. (Maplewood, MN); Schmoeckel, Alison K. (Stillwater, MN); Vernstrom, George D. (Cottage Grove, MN); Atanasoski, Radoslav (Edina, MN); Wood, Thomas E. (Stillwater, MN); Yang, Ruizhi (Halifax, CA); Easton, E. Bradley (Halifax, CA); Dahn, Jeffrey R. (Hubley, CA); O' Neill, David G. (Lake Elmo, MN)

    2011-03-22

    An oxygen-reducing catalyst layer, and a method of making the oxygen-reducing catalyst layer, where the oxygen-reducing catalyst layer includes a catalytic material film disposed on a substrate with the use of physical vapor deposition and thermal treatment. The catalytic material film includes a transition metal that is substantially free of platinum. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.

  9. 基于神经网络和遗传算法的池塘溶解氧预测模型%A prediction model for dissolved oxygen level in a fish pond based on combination of neural network and genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    缪新颖; 葛廷友; 高; 王建彬

    2011-01-01

    水产养殖池塘是一个多变量、非线性和大时延系统,其中溶解氧的预测也是一个复杂的问题.针对大连某水产养殖池塘,作者建立了一个基于Levenberg-Marquardt(LM)神经网络和遗传算法(GA)的溶解氧预测模型GA-LM,并将该模型与传统的BP神经网络进行比较分析.结果表明:使用本研究中建立的GA-LM模型预测的溶解氧值和实际测定值吻合较好,预测更为精准,运行时间明显减少.%The prediction of dissolved oxygen (DO) level is complicated in aquaculture ponds as a complex system with multi-variables, nonlinearity and long-time lag. In this study, GA-LM, a hybrid neural network model combining Levenberg Marquardt(LM) algorithm and Genetic Algorithm (GA) was developed for DO level predicting in an aquaculture pond at Dalian, China. The The comparison of performance of GA-LM with the conventional Back -Propagation (BP) algorithm revealed that the predicted DO values using GA-LM model are in good agreement with the measured data, indicating that the model is capable of predicting DO accurately and rapidly.

  10. Integration of oxygen membranes for oxygen production in cement plants

    DEFF Research Database (Denmark)

    Puig Arnavat, Maria; Søgaard, Martin; Hjuler, Klaus;

    2015-01-01

    The present paper describes the integration of oxygen membranes in cement plants both from an energy, exergy and economic point of view. Different configurations for oxygen enrichment of the tertiary air for combustion in the pre-calciner and full oxy-fuel combustion in both pre-calciner and kiln...

  11. 高压氧联合神经节苷脂对脑出血患者凝血酶、血清髓鞘碱性蛋白、D-二聚体的影响%Effect of hyperbaric oxygen combined with ganglion glycosides on thrombin, serum myelin basic protein and D-dimer in patients with intracerebral hemorrhage

    Institute of Scientific and Technical Information of China (English)

    陈伟; 王茂德; 王宁; 鲍刚; 王拓

    2016-01-01

    Objective To observe the effect of hyperbaric oxygen combined with ganglion glycosides on thrombin, se-rum myelin basic protein and D-dimer in patients with intracerebral hemorrhage.Methods Selected from June 2014 to June 2015, 100 cases of cerebral hemorrhage patients in Xi'an Jiaotong University First Affiliated Hospital neurosurgery department as the research object, according to the order of admission, they were randomly divided into control group and observation group, each group of 50 cases, on the basis of conventional therapy patients in control group were treated with ganglioside treatment, the observation group given hyperbaric oxygen combined with ganglioside treatment.Before and after treatment, thrombin, serum myelin basic protein, D-dimer, hematoma volume, neurological function defect score ( NIHSS) , daily life a-bility score ( ADL) were observed, and the clinical effect was evaluated.Results Before treatment, 2 groups of thrombin, serum myelin basic protein ( MBP) , D-dimer, volume of hematoma, NIHSS and ADL score differences had no statistical sig-nificance ( P >0.05), after treatment, two groups of thrombin, serum myelin basic protein (MBP), D-dimer, hematoma volume and NIHSS score compared with those before treatment were significantly decreased ( P <0.05), ADL score before treatment were significantly higher ( P <0.05) , and the observation group was more obvious than that of the control group, the above indicators improved ( P <0.05).The control group cured rate, significant progress rate, improvement rate were 24.00%, 36.00%, 24.00%, the observation group were 30.00%and 40.00%, 24.00%observed group, the total efficien-cy is remarkably higher than that of the control group (94.00%vs.84.00%,χ2 =3.55, P <0.05).Conclusion Hyperbaric oxygen combined with ganglion glycosides can reduce the level of thrombin, serum myelin basic protein and D-dimer levels in patients with cerebral hemorrhage,and improve the therapeutic effect.%目的:观察高压

  12. Limitations of potentiometric oxygen sensors operating at low oxygen levels

    DEFF Research Database (Denmark)

    Lund, Anders; Jacobsen, Torben; Hansen, Karin Vels;

    2011-01-01

    The electrochemical processes that limit the range of oxygen partial pressures in which potentiometric oxygen sensors can be used, were analysed using a theoretical and an experimental approach. Electrochemical impedance spectroscopy was performed on porous Pt/yttria stabilised zirconia (YSZ......) electrodes between 10−6 and 0.2 bar and at temperatures between 500 and 950 °C. The flow of oxide ions and electron holes through a sensor cell, with a YSZ electrolyte, were calculated under similar conditions. The oxygen permeation of the sensor cell was insignificant at an oxygen partial pressure of 10......−6 bar for an inlet flow rate higher than 2 L h−1 between 600 and 800 °C. The polarisation resistance measured between 10−6 and 10−4 bar was found to be inversely proportional to the oxygen partial pressure, nearly temperature independent and inversely proportional to the inlet gas flow rate, which shows...

  13. Therapy strategy of extracorporeal membrane oxygenation (ECMO) combine with intra aortic balloon pump (IABP), continuous renal replacement therapy (CRRT) and respiratory machine in serious condition cardiac surgery cases%危重症心脏外科患者的ECMO辅助技术与IABP、CRRT、呼吸机的相互配合治疗策略

    Institute of Scientific and Technical Information of China (English)

    张海波; 孟旭; 韩杰; 李岩; 贾一新; 许春雷; 曾文; 王坚刚; 艾米儿

    2014-01-01

    Objective To investigate clinic results of the extracorporeal membrane oxygenation (ECMO) technique combine with Intro aortic balloon pump (IABP),Continuous renal replacement therapy (CRRT),respiratory machine therapy in the serious condition cardiac surgery cases.Methods From 2004 to 2009 all data of the cases received the ECMO therapy were analyzed retrospectively.Results Totally 180 cases were treated with extracorporeal membrane oxygenation (ECMO) technique in this period of time with weaning rate of 68.9% and survival rate of 72.8%.Besides of the of replacing rountine CPB 69 cases,49 cases died in the 111 cases of routine used ECMO cases (survival rate 55.9%).There were 40 cases treated with ECMO combined with IABP in which 23 cases died (survival rate 42.5%).After the first use of IABP 28 cases were treated with ECMO because of hemodynamic instability and 9 died (survival rate 54%).After the first use of ECMO because of severe valve disease or hemodynamic instability after heart transplantation,or emergency cardiopulmonary resuscitation and the IABP was admitted in 12 cases for the small pulse pressure,decreased left ventricular contraction (10 died,survival rate 36.1%).48 cases were treated with ECMO combined with CRRT (total survival rate 40%).In these cases 6 cases were treated with CRRT first and 4 cases died (survival rate 33.3%).And 42 cases received the ECMO first and 25 cases died (survival rate 47.9%).In the total series 19 cases were treated with ECMO combined with IABP,CRRT,respiratory machine and 12 cases died (survival rate 36.1%).Conclusion ECMO is an effective technique for the heart failure after cardiac surgery,the earlier use may bring earlier recovery of the heart function.Combine administration of ECMO,CRRT,IABP and respiratory machine may be adopted for the multiple organs failure cases with attention of the coordinate and weaning orders among the machines.%目的 探讨危重症心脏外科术后患者联合体外膜

  14. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; Q. Cai; J. Yang; W.B. Yelon; W.J. James; H.U. Anderson; Alan Jacobson; C.A. Mims

    2004-10-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In this report, Moessbauer spectroscopy was used to study the local environmentals of LSFT with various level of oxygen deficiency. Ionic valence state, magnetic interaction and influence of Ti on superexchange are discussed Stable crack growth studies on Dense OTM bars provided by Praxair were done at elevated temperature, pressure and elevated conditions. Post-fracture X-ray data of the OTM fractured at 1000 C in environment were refined by FullProf code and results indicate a distortion of the parent cubic perovskite to orthorhombic structure with reduced symmetry. TGA-DTA studies on the post-fracture samples also indicated residual effect arising from the thermal and stress history of the samples. An electrochemical cell has been designed and built for measurements of the Seebeck coefficient as a function of temperature and pressure. The initial measurements on La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} are reported. Neutron diffraction measurements of the same composition are in agreement with both the stoichiometry and the kinetic behavior observed in coulometric titration measurements. A series of isotope transients under air separation mode (small gradient) were completed on the membrane of LSCrF-2828 at 900 C. Low pO{sub 2} atmospheres based on with CO-CO{sub 2} mixtures have also been admitted to the delivery side of the LSCrF-2828 membrane to produce the gradients which exist under syngas generation conditions. The COCO{sub 2} mixtures have normal isotopic {sup 18}O abundances. The evolution of {sup 18}O on the delivery side in these experiments after an {sup 18}O pulse on the air side reveals a wealth of information about the oxygen transport processes.

  15. Body mass scaling of passive oxygen diffusion in endotherms and ectotherms.

    Science.gov (United States)

    Gillooly, James F; Gomez, Juan Pablo; Mavrodiev, Evgeny V; Rong, Yue; McLamore, Eric S

    2016-05-10

    The area and thickness of respiratory surfaces, and the constraints they impose on passive oxygen diffusion, have been linked to differences in oxygen consumption rates and/or aerobic activity levels in vertebrates. However, it remains unclear how respiratory surfaces and associated diffusion rates vary with body mass across vertebrates, particularly in relation to the body mass scaling of oxygen consumption rates. Here we address these issues by first quantifying the body mass dependence of respiratory surface area and respiratory barrier thickness for a diversity of endotherms (birds and mammals) and ectotherms (fishes, amphibians, and reptiles). Based on these findings, we then use Fick's law to predict the body mass scaling of oxygen diffusion for each group. Finally, we compare the predicted body mass dependence of oxygen diffusion to that of oxygen consumption in endotherms and ectotherms. We find that the slopes and intercepts of the relationships describing the body mass dependence of passive oxygen diffusion in these two groups are statistically indistinguishable from those describing the body mass dependence of oxygen consumption. Thus, the area and thickness of respiratory surfaces combine to match oxygen diffusion capacity to oxygen consumption rates in both air- and water-breathing vertebrates. In particular, the substantially lower oxygen consumption rates of ectotherms of a given body mass relative to those of endotherms correspond to differences in oxygen diffusion capacity. These results provide insights into the long-standing effort to understand the structural attributes of organisms that underlie the body mass scaling of oxygen consumption.

  16. 负压封闭引流联合含氧液冲洗对下肢慢性静脉性溃疡患者创面的影响%Effects of vacuum sealing drainage combined with irrigation of oxygen loaded fluid on wounds of patients with chronic venous leg ulcers

    Institute of Scientific and Technical Information of China (English)

    温皇鼎; 李志清; 张美光; 王甲汉; 王桂芳; 吴起; 童森

    2015-01-01

    Objective To evaluate the therapeutic effects of VSD combined with irrigation of oxygen loaded fluid on the growth of granulation tissue and macrophage polarization in chronic venous leg ulcers.Methods Thiry-four patients with chronic venous leg ulcers hospitalized in our department from December 2010 to July 2014 were divided into VSD group (A,n =11),VSD+irrigation group (B,n =11),and VSD + oxygen loaded fluid irrigation group (C,n =12) according to the random number table.After admission,debridement was performed,and granulation tissue in the center of the wound was harvested during the operation.After debridement,the patients in group A were treated with VSD only (negative pressure from -30 to-25 kPa,the same below) ; the patients in group B were treated with VSD combining irrigation of normal saline; the patients in group C were treated with VSD combining normal saline loaded with oxygen irrigation (flow of 1 L/min).On post treatment day (PTD) 7,the VSD devices were removed.Gross observation was conducted before debridement and on PTD 7.Ou PTD 7,the granulation tissue in the center of the wound was harvested for histopathological observation with HE staining and Masson staining,following calculation of granulation tissue coverage rate.After debridement but before the negative pressure therapy (hereinafter referred to as before treatment) and on PTD 7,partial pressure of oxygen of the skin around the wound was measured by transcutaneous tissue oxygen tension survey meter.On PTD 7,expression of vascular endothelial growth factor (VEGF) was determined with immunohistochemistry.Before treatment and on PTD 7,cells with double positive expressions of induced nitric oxide synthase plus CD68 (type Ⅰ macrophage) and arginase 1 plus CD68 (type Ⅱ macrophage) were observed with immunofluorescence staining and quantified.Data were processed with Fisher's exact test,one-way analysis of variance,covariance analysis,paired t test,and LSD test.Results (1) The gross

  17. Tryptophan oxygenation: mechanistic considerations.

    Science.gov (United States)

    Naismith, James H

    2012-06-01

    From a protein structural viewpoint, tryptophan is often considered an inert structural amino acid, playing a role as a hydrophobic anchor in membrane proteins or as part of the hydrophobic core of soluble proteins. However, tryptophan is the only polyaromatic amino acid and, from a chemical viewpoint, possesses unique reactivity owing to the electron-richness of the indole system. This reactivity is seen in the area of natural products and metabolites which have exquisite modifications of the indole ring system. Enzymes have evolved multiple strategies to break or modify the indole ring; one particular class is the IDO/TDO (indoleamine/tryptophan dioxygenase) superfamily. A new member of this family, PrnB, on the surface catalyses a very different reaction, but actually shares much of the early chemistry with the tryptophan dioxygenases. Studies on PrnB have contributed to our understanding of the wider superfamily. In the present mini-review, recent developments in our understanding of how the TDO class of enzymes use activated molecular oxygen to break the indole ring are discussed.

  18. Oxygen detection using evanescent fields

    Science.gov (United States)

    Duan, Yixiang; Cao, Weenqing

    2007-08-28

    An apparatus and method for the detection of oxygen using optical fiber based evanescent light absorption. Methylene blue was immobilized using a sol-gel process on a portion of the exterior surface of an optical fiber for which the cladding has been removed, thereby forming an optical oxygen sensor. When light is directed through the optical fiber, transmitted light intensity varies as a result of changes in the absorption of evanescent light by the methylene blue in response to the oxygen concentration to which the sensor is exposed. The sensor was found to have a linear response to oxygen concentration on a semi-logarithmic scale within the oxygen concentration range between 0.6% and 20.9%, a response time and a recovery time of about 3 s, ant to exhibit good reversibility and repeatability. An increase in temperature from 21.degree. C. to 35.degree. C. does not affect the net absorption of the sensor.

  19. Low-oxygen waters limited habitable space for early animals

    Science.gov (United States)

    Tostevin, R.; Wood, R. A.; Shields, G. A.; Poulton, S. W.; Guilbaud, R.; Bowyer, F.; Penny, A. M.; He, T.; Curtis, A.; Hoffmann, K. H.; Clarkson, M. O.

    2016-09-01

    The oceans at the start of the Neoproterozoic Era (1,000-541 million years ago, Ma) were dominantly anoxic, but may have become progressively oxygenated, coincident with the rise of animal life. However, the control that oxygen exerted on the development of early animal ecosystems remains unclear, as previous research has focussed on the identification of fully anoxic or oxic conditions, rather than intermediate redox levels. Here we report anomalous cerium enrichments preserved in carbonate rocks across bathymetric basin transects from nine localities of the Nama Group, Namibia (~550-541 Ma). In combination with Fe-based redox proxies, these data suggest that low-oxygen conditions occurred in a narrow zone between well-oxygenated surface waters and fully anoxic deep waters. Although abundant in well-oxygenated environments, early skeletal animals did not occupy oxygen impoverished regions of the shelf, demonstrating that oxygen availability (probably >10 μM) was a key requirement for the development of early animal-based ecosystems.

  20. Dissolved oxygen imaging to investigate biodegradation at lab scale

    Science.gov (United States)

    Lerner, D. N.; Rees, H.; Huang, W. E.; Smith, C. C.; Oswald, S. E.

    2003-04-01

    A novel combination of a non-invasive imaging method with an oxygen sensitive fluorescent indicator was developed to investigate the biodegradation processes occurring at the fringe of a solute plume. A thin transparent porous matrix was made from quartz plates and quartz sand and acetate was continuously injected in the uniform flow field containing dissolved oxygen. Ruthenium (II)-dichlorotris(1,10-phenanthroline) (Ru(phen)3Cl2), a water soluble fluorescent dye, was used as an indicator of dissolved oxygen concentration as its fluorescence intensity is dependent on the concentration of oxygen. The oxygen distribution within the matrix was interpreted from images recorded by a CCD camera. These two-dimensional experimental results show quantitatively how the oxygen concentrations decrease strongly at the narrow plume fringe and that oxygen was exhausted at the core of the plume. Separately, dispersivity was measured in a series of non-reactive transport experiments, and biodegradation parameters were evaluated by batch experiments. This measurement method provides a novel approach to investigate details of behavior of solute transport and biodegradation in porous media.

  1. Combination analysis.

    Science.gov (United States)

    Tallarida, Ronald J

    2010-01-01

    This chapter describes quantitative methodology that is directed toward assessing interactions between a combination of agonist drugs that individually produce overtly similar effects. Drugs administered in combination may show exaggerated, reduced or predictable effects that are dependent on the specific drug pair and the doses of t h e constituents. The basisfor quantitating these unusual interactions is the concept of dose equivalence which, in turn, is determined from the individual drug dose-effect relations. A common analytical procedure that follows from dose equivalence uses a graph termed an isobologram. We present here an overview of the isobologram, its use and certain related methods that apply to classifying various drug interactions.

  2. Cerebral oxygenation is reduced during hyperthermic exercise in humans

    DEFF Research Database (Denmark)

    Rasmussen, P.; Nybo, Lars; Volianitis, Stefanos;

    2010-01-01

    Abstract Aim: Cerebral mitochondrial oxygen tension (P(mito)O(2)) is elevated during moderate exercise, while it is reduced when exercise becomes strenuous, reflecting an elevated cerebral metabolic rate for oxygen (CMRO(2)) combined with hyperventilation-induced attenuation of cerebral blood flow...... (CBF). Heat stress challenges exercise capacity as expressed by increased rating of perceived exertion (RPE). Methods: This study evaluated the effect of heat stress during exercise on P(mito)O(2) calculated based on a Kety-Schmidt-determined CBF and the arterial-to-jugular venous oxygen differences...... in eight males [27 +/- 6 years (mean +/- SD) and maximal oxygen uptake (VO(2max)) 63 +/- 6 mL kg(-1) min(-1)]. Results: The CBF, CMRO(2) and P(mito)O(2) remained stable during 1 h of moderate cycling (170 +/- 11 W, approximately 50% of VO(2max), RPE 9-12) in normothermia (core temperature of 37.8 +/- 0...

  3. Paradox reconsidered: Methane oversaturation in well-oxygenated lake waters

    DEFF Research Database (Denmark)

    Tang, Kam W.; McGinnis, Daniel F.; Frindte, Katharina;

    2014-01-01

    The widely reported paradox of methane oversaturation in oxygenated water challenges the prevailing paradigm that microbial methanogenesis only occurs under anoxic conditions. Using a combination of field sampling, incubation experiments, and modeling, we show that the recurring mid-water methane...... peak in Lake Stechlin, northeast Germany, was not dependent on methane input from the littoral zone or bottom sediment or on the presence of known micro-anoxic zones. The methane peak repeatedly overlapped with oxygen oversaturation in the seasonal thermocline. Incubation experiments and isotope...... analysis indicated active methane production, which was likely linked to photosynthesis and/or nitrogen fixation within the oxygenated water, whereas lessening of methane oxidation by light allowed accumulation of methane in the oxygen-rich upper layer. Estimated methane efflux from the surface water...

  4. Properties of Reactive Oxygen Species by Quantum Monte Carlo

    CERN Document Server

    Zen, Andrea; Guidoni, Leonardo

    2014-01-01

    The electronic properties of the oxygen molecule, in its singlet and triplet states, and of many small oxygen-containing radicals and anions have important roles in different fields of Chemistry, Biology and Atmospheric Science. Nevertheless, the electronic structure of such species is a challenge for ab-initio computational approaches because of the difficulties to correctly describe the statical and dynamical correlation effects in presence of one or more unpaired electrons. Only the highest-level quantum chemical approaches can yield reliable characterizations of their molecular properties, such as binding energies, equilibrium structures, molecular vibrations, charge distribution and polarizabilities. In this work we use the variational Monte Carlo (VMC) and the lattice regularized Monte Carlo (LRDMC) methods to investigate the equilibrium geometries and molecular properties of oxygen and oxygen reactive species. Quantum Monte Carlo methods are used in combination with the Jastrow Antisymmetrized Geminal ...

  5. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; T. Nithyanantham; X.-D Zhou; Y-W. Sin; H.U. Anderson; Alan Jacobson; C.A. Mims

    2005-11-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In the current research, the electrical conductivity and Seebeck coefficient were measured as a function of temperature in air. Based on these measurements, the charge carrier concentration, net acceptor dopant concentration, activation energy of conduction and mobility were estimated. The studies on the fracture toughness of the LSFT and dual phase membranes at room temperature have been completed and reported previously. The membranes that are exposed to high temperatures at an inert and a reactive atmosphere undergo many structural and chemical changes which affects the mechanical properties. To study the effect of temperature on the membranes when exposed to an inert environment, the membranes (LAFT and Dual phase) were heat treated at 1000 C in air and N{sub 2} atmosphere and hardness and fracture toughness of the membranes were studied after the treatment. The indentation method was used to find the fracture toughness and the effect of the heat treatment on the mechanical properties of the membranes. Further results on the investigation of the origin of the slow kinetics on reduction of ferrites have been obtained. The slow kinetics appears to be related to a non-equilibrium reduction pathway that initially results in the formation of iron particles. At long times, equilibrium can be reestablished with recovery of the perovskite phase. 2-D modeling of oxygen movement has been undertaken in order to fit isotope data. The model will serve to study ''frozen'' profiles in patterned or composite membranes.

  6. Monitoring Cerebral Oxygenation in Neonates: An Update

    Science.gov (United States)

    Dix, Laura Marie Louise; van Bel, Frank; Lemmers, Petra Maria Anna

    2017-01-01

    Cerebral oxygenation is not always reflected by systemic arterial oxygenation. Therefore, regional cerebral oxygen saturation (rScO2) monitoring with near-infrared spectroscopy (NIRS) is of added value in neonatal intensive care. rScO2 represents oxygen supply to the brain, while cerebral fractional tissue oxygen extraction, which is the ratio between rScO2 and systemic arterial oxygen saturation, reflects cerebral oxygen utilization. The balance between oxygen supply and utilization provides insight in neonatal cerebral (patho-)physiology. This review highlights the potential and limitations of cerebral oxygenation monitoring with NIRS in the neonatal intensive care unit. PMID:28352624

  7. Combination rules

    NARCIS (Netherlands)

    Holicky, M.; Vrouwenvelder, A.C.W.M.

    2002-01-01

    Load combinations specified in EN 1990 for verification of ultimate limit and serviceability limit states in conjunction with the partial factor method are discussed and illustrated by practical examples of typical civil structures. Alternative procedures to identify critical load cases are reviewed

  8. Oxygenates vs. synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Kamil Klier; Richard G. Herman; Alessandra Beretta; Maria A. Burcham; Qun Sun; Yeping Cai; Biswanath Roy

    1999-04-01

    Methanol synthesis from H{sub 2}/CO has been carried out at 7.6 MPa over zirconia-supported copper catalysts. Catalysts with nominal compositions of 10/90 mol% and 30/70 mol% Cu/ZrO{sub 2} were used in this study. Additionally, a 3 mol% cesium-doped 10/90 catalyst was prepared to study the effect of doping with heavy alkali, and this promoter greatly increased the methanol productivity. The effects of CO{sub 2} addition, water injection, reaction temperature, and H{sub 2}/C0 ratio have been investigated. Both CO{sub 2} addition to the synthesis gas and cesium doping of the catalyst promoted methanol synthesis, while inhibiting the synthesis of dimethyl ether. Injection of water, however, was found to slightly suppress methanol and dimethyl ether formation while being converted to CO{sub 2} via the water gas shift reaction over these catalysts. There was no clear correlation between copper surface area and catalyst activity. Surface analysis of the tested samples revealed that copper tended to migrate and enrich the catalyst surface. The concept of employing a double-bed reactor with a pronounced temperature gradient to enhance higher alcohol synthesis was explored, and it was found that utilization of a Cs-promoted Cu/ZnO/Cr{sub 2}O{sub 3} catalyst as a first lower temperature bed and a Cs-promoted ZnO/Cr{sub 2}O{sub 3} catalyst as a second high-temperature bed significantly promoted the productivity of 2-methyl-1-propanol (isobutanol) from H{sub 2}/CO synthesis gas mixtures. While the conversion of CO to C{sub 2+} oxygenates over the double-bed configuration was comparable to that observed over the single Cu-based catalyst, major changes in the product distribution occurred by the coupling to the zinc chromite catalyst; that is, the productivity of the C{sub 1}-C{sub 3} alcohols decreased dramatically, and 2-methyl branched alcohols were selectively formed. The desirable methanol/2-methyl oxygenate molar ratios close to 1 were obtained in the present double

  9. Advanced Oxygen Systems for Aircraft (Systemes d’Oxygene Avances)

    Science.gov (United States)

    1996-04-01

    son acheminement vers le convertisseur embarque, ainsi que la plus grande fiabilite de 1’OBOGS compare aux systemes ä oxygene liquide traditionnels...Standardisation Coordination Committee. Minimum Physiological Requirements for Aircrew Demand Breathing Systems. Air Standard 61/101/6A, Washington DC ...Washington DC 1981. 5. Ernsting J, and Stewart WK, Introduction to Oxygen Deprivation at Reduced Barometric Pressure in: Gilles JA, Ed., A Textbook of

  10. 磷酸肌酸钠联合高压氧治疗一氧化碳中毒迟发性脑病疗效观察%Curative effect observation of creatine phosphate sodium combined with high pressure oxygen in the treatment of chronic encephalopathy of carbon monoxide poisoning

    Institute of Scientific and Technical Information of China (English)

    李伟; 台立稳

    2016-01-01

    Objective:To explore the curative effect of creatine phosphate sodium combined with high pressure oxygen in the treatment of chronic encephalopathy of carbon monoxide poisoning(DEACMP).Methods:43 patients with DEACMP were selected. They were randomly divided into the treatment group and the control group.Patients in the control group were given conventional treatment.Patients in the treatment group were given injection creatine phosphate sodium treatment on the basis of the control group.The curative effects of two groups were observed.Results:The cure rate and effective rate of the treatment group were significantly higher than those of the control group,and the differences were statistically significant(P<0.05).Conclusion:The creatine phosphate sodium can improve the cell energy supply of DEACMP patients,protect the brain function,improve the hypoxia tolerance of brain cells,improve the life quality of DEACMP patients.%目的:探讨磷酸肌酸钠联合高压氧治疗一氧化碳中毒迟发性脑病(DEACMP)的疗效。方法:收治DEACMP患者43例,随机分为治疗组和对照组。对照组给予常规治疗,治疗组则在对照组的基础上加注射用磷酸肌酸钠治疗。观察两组患者的疗效。结果:治疗组治愈率及有效率均明显高于对照组,差异有统计学意义(P<0.05)。结论:磷酸肌酸钠可以改善DEACMP患者的细胞能量供应,保护脑功能,提高脑细胞对缺氧的耐受性,提高DEACMP患者的生活质量。

  11. Combination Light

    Science.gov (United States)

    1990-01-01

    The Rayovac TANDEM is an advanced technology combination work light and general purpose flashlight that incorporates several NASA technologies. The TANDEM functions as two lights in one. It features a long range spotlight and wide angle floodlight; simple one-hand electrical switching changes the beam from spot to flood. TANDEM developers made particular use of NASA's extensive research in ergonomics in the TANDEM's angled handle, convenient shape and different orientations. The shatterproof, water resistant plastic casing also draws on NASA technology, as does the shape and beam distance of the square diffused flood. TANDEM's heavy duty magnet that permits the light to be affixed to any metal object borrows from NASA research on rare earth magnets that combine strong magnetic capability with low cost. Developers used a NASA-developed ultrasonic welding technique in the light's interior.

  12. Combining haplotypers

    CERN Document Server

    Kääriäinen, Matti; Lappalainen, Sampsa; Mielikäinen, Taneli

    2007-01-01

    Statistically resolving the underlying haplotype pair for a genotype measurement is an important intermediate step in gene mapping studies, and has received much attention recently. Consequently, a variety of methods for this problem have been developed. Different methods employ different statistical models, and thus implicitly encode different assumptions about the nature of the underlying haplotype structure. Depending on the population sample in question, their relative performance can vary greatly, and it is unclear which method to choose for a particular sample. Instead of choosing a single method, we explore combining predictions returned by different methods in a principled way, and thereby circumvent the problem of method selection. We propose several techniques for combining haplotype reconstructions and analyze their computational properties. In an experimental study on real-world haplotype data we show that such techniques can provide more accurate and robust reconstructions, and are useful for out...

  13. Search Combinators

    CERN Document Server

    Schrijvers, Tom; Wuille, Pieter; Samulowitz, Horst; Stuckey, Peter J

    2012-01-01

    The ability to model search in a constraint solver can be an essential asset for solving combinatorial problems. However, existing infrastructure for defining search heuristics is often inadequate. Either modeling capabilities are extremely limited or users are faced with a general-purpose programming language whose features are not tailored towards writing search heuristics. As a result, major improvements in performance may remain unexplored. This article introduces search combinators, a lightweight and solver-independent method that bridges the gap between a conceptually simple modeling language for search (high-level, functional and naturally compositional) and an efficient implementation (low-level, imperative and highly non-modular). By allowing the user to define application-tailored search strategies from a small set of primitives, search combinators effectively provide a rich domain-specific language (DSL) for modeling search to the user. Remarkably, this DSL comes at a low implementation cost to the...

  14. 上肢康复机器人联合高压氧对脑卒中偏瘫患者上肢功能的影响%Effects of upper limb rehabilitation robot combined with hyperbaric oxygen in the recovery of upper limb function in stroke patients with hemiplegia

    Institute of Scientific and Technical Information of China (English)

    孟庆芳; 何勤; 刘依凌; 张东玲

    2015-01-01

    目的 探讨上肢康复机器人联合高压氧(hyperbaric oxygen,HBO)对脑卒中偏瘫患者上肢功能的疗效.方法 将150例脑卒中偏瘫患者依患者意愿分为HBO组、机器人组及综合治疗组,3组患者均接受基础药物和常规康复治疗;HBO组在此基础上辅以HBO治疗,机器人组辅以上肢康复机器人训练,综合治疗组则辅以HBO治疗及上肢康复机器人训练.治疗时间1个月,治疗前后分别进行简易上肢功能检测(STEF)、Fugl-Meyer上肢运动功能评分(FMA)、改良Barthel指数(MBI)评分,由专人进行双盲评定.结果 治疗前3组患者的STEF、上肢FMA及MBI评分组间差异无统计学意义(P>0.05);经1个月治疗后,各组上述指标均较治疗前明显改善(P<0.05),并以综合治疗组的改善幅度尤为显著(STEF:治疗后68.4±6.9,治疗前15.8±16.2;FMA:治疗后56.4±6.9,治疗前20.6±4.2;MBI:治疗后76.7 ±22.7,治疗前22.7 ±6.5),机器人组次之,HBO组相对较差,各指标组间差异均具有统计学意义(P<0.05).结论 上肢康复机器人联合HBO治疗能进一步改善脑卒中偏瘫患者上肢功能,提高生活质量,该疗法值得临床推广、应用.%Objective To investigate the therapeutic effects of upper limb rehabilitation robot combined with hyperbaric oxygen(HBO) in the rehabilitation of upper limb in stroke patients with hemiplegia.Methods One hundred and fifty cases of stroke patients with hemiplegia were randomly divided into 3 groups,the hyperbaric oxygen (HBO)group,the robot group and the comprehensive treatment group.The patients in the 3 groups all received basic drug and conventional rehabilitation treatment.The patients in the HBO group were treated with HBO;the patients in the robot group were additionally supplemented by upper limb rehabilitation robot training;and the patients in the comprehensive treatment group were supplemented by HBO as well as upper limb rehabilitation robot training.The treatment lasted for one

  15. Early Oxygen-Utilization and Brain Activity in Preterm Infants

    NARCIS (Netherlands)

    Tataranno, ML; Alderliesten, Thomas; De Vries, Linda S.; Groenendaal, Floris; Toet, MC; Lemmers, Petra M A; van de Vosse, R.; Van Bel, Frank; Benders, Manon J N L

    2015-01-01

    The combined monitoring of oxygen supply and delivery using Near-InfraRed spectroscopy (NIRS) and cerebral activity using amplitude-integrated EEG (aEEG) could yield new insights into brain metabolism and detect potentially vulnerable conditions soon after birth. The relationship between NIRS and qu

  16. Microsensor Studies of Oxygen and Light-Distribution in the Green Macroalga Codium Fragile

    DEFF Research Database (Denmark)

    LASSEN, C.; BEBOUT, LE; PAERL, HW;

    1994-01-01

    Scalar irradiance, oxygen concentration, and oxygenic photosynthesis were measured at 0.1 mm spatial resolution within the tissue of the siphonous green macroalga Codium fragile subsp. tomentosoides (van Goer) Silva by fiber-optic scalar irradiance microsensors and oxygen microelectrodes, The sca......Scalar irradiance, oxygen concentration, and oxygenic photosynthesis were measured at 0.1 mm spatial resolution within the tissue of the siphonous green macroalga Codium fragile subsp. tomentosoides (van Goer) Silva by fiber-optic scalar irradiance microsensors and oxygen microelectrodes...... to multiple scattering in the medullary tissue. The constant intensity of visible light below 0.2 mm was thus a result of the combined effects of absorption and backscattering from the medulla. The oxygen exchange between the alga and the surrounding water was diffusion-limited with a steep O-2 gradient...

  17. Oxygen-Methane Thruster Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Two main innovations will be developed in the Phase II effort that are fundamentally associated with our gaseous oxygen/gaseous methane RCS thruster. The first...

  18. The Measurement of Dissolved Oxygen

    Science.gov (United States)

    Thistlethwayte, D.; And Others

    1974-01-01

    Describes an experiment in environmental chemistry which serves to determine the dissolved oxygen concentration in both fresh and saline water. Applications of the method at the undergraduate and secondary school levels are recommended. (CC)

  19. Observation on the curative effect of the stroke unit combined with hyperbaric oxygen in the treatment of conscious disorder associated with acute cerebral hemorrhage%卒中单元联合高压氧治疗急性脑出血意识障碍的疗效观察

    Institute of Scientific and Technical Information of China (English)

    王轶群; 夏添; 杨世泉; 余本松; 程晋成

    2015-01-01

    Objective To observe the clinical effect of the stroke unit combined with hyperbaric oxygen (HBO) in the treatment of patients with conscious disorder associated with acute cerebral hemorrhage . Methods The patients were divided into the stroke unit group (or the SU group) and the control group.Thepatients of the 2 groups all received routine mini-traumatic trepanation and drug treatment.In addition, thecontrol group received routine medical treatment , HBO therapy and rehabilitation treatment, while the SU groupreceived comprehensive rehabilitation treatment and HBO therapy in accordance with standard operatingprocedures.Clinical therapeutic effects both before and after treatment were compared between the 2 groups,evaluated with Glasgow coma scale (GCS) scores and neurologic impairment scores, and changes in cerebralvascular function were detected as well.Results After treatment, neurological impairment of the SU group(6.57 ±2.24)was improved more significantly than that of the control group (8.93 ±3.41).GCS scores of theSU group(14.56 ±2.71) were significantly increased than those of the control group (10.25 ±2.32).Inaddition, the indexes of cerebral vascular function were greatly improved , with that of the SU group beingobviously better than that of the control group .Conclusions Stroke unit treatment combined with HBO couldsignificantly improve conscious disorder of the patients associated with acute cerebral hemorrhage , and thetherapeutic efficacy was significantly superior to that of ordinary hospitalization mode .%目的:观察卒中单元联合高压氧治疗急性脑出血伴发意识障碍患者的临床疗效。方法将500例研究对象分为卒中单元组(stroke unit,SU组,280例)和对照组(220例),均常规采用颅内血肿微创清除术及药物治疗,对照组采用常规内科及高压氧和康复治疗,卒中单元组按标准化操作程序,给予综合康复及高压氧治疗。在治疗前后通过Glasgow评

  20. 可调节封闭式负压引流技术联合局部氧疗对兔深Ⅱ度烫伤创面愈合的影响%Influence of Regulated Negative Pressure-Assisted Wound Therapy Combined with Topical Oxygen Therapy on the Healing of Deep Second Degree Scalded Rabbits

    Institute of Scientific and Technical Information of China (English)

    胡晓东; 李永忠; 李云飞; 陈莉; 蒋朔

    2015-01-01

    目的探讨可调节封闭式负压引流技术联合局部氧疗对兔深Ⅱ度烫伤创面愈合的影响,为临床应用提供实验依据。方法以40只新西兰大白兔为研究对象,建立兔深Ⅱ度烫伤模型,并将创伤兔随机分为A组(常规包扎治疗)、B组(局部氧疗)、C组(可调节封闭式负压引流治疗)、D组(可调节封闭式负压+局部氧疗),观察创面的大体变化及愈合情况,记录各组创面愈合率、愈合时间。结果 A组平均愈合天数是(25.2±2.1)d,B组平均愈合天数是(23.6±1.8)d,C组的平均愈合天数是(19.8±2.2)d,D组的平均愈合天数是(16.6±1.4)d,A组与其他三组在创面愈合时间差异上有统计学意义。治疗第12~18d,A组与其他三组在创面愈合率差异上有统计学意义。结论可调节封闭式负压引流技术与局部氧疗相结合能促进兔深Ⅱ度烫伤创面愈合,是一种新的治疗深Ⅱ度烫伤创面的方式。%Objective To probe into the influence of Negative Pressure-Assisted Wound Therapy (RNPT) combined with Topical Oxygen Therapy (TOT) on the healing of deep second degree scalded rabbits as to provide a experimental basis for clinical application. Methods Animal models of deep second degree scalded wound were established in 40 New Zealand rabbits, which were randomly divided into four groups:group A (routine enswathement), group B (TOT), group C (RNPT) and group D (RNPT +TOT).the changes in the wound were observed, Wound healing rate and time were respectively recorded. Results The wound healing time in group D was (16.6±1.4)d,which was significantly dif erent from those of the other groups, wound healing rate was also statistical y dif erent between group D and other groups from the 12th day to 18th day after treatment. Conclusion The new combined therapy of RNPT and TOT Can facilitate deep second degree scalded wound healing.

  1. Wet steam treatment with oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Ruehle, W.; Enkler, G. [EnBW Kraftwerke AG, Kernkraftwerk Philippsburg (Germany)

    1999-07-01

    After many years of excellent results using high all volatile treatment (HAVT) for operation of the secondary system of a PWR, flow assisted corrosion in the heating pipes of the intermediate steam reheaters has been experienced. Oxygen addition into the heating steam before the reheater is expected to improve the protective oxide layers formation. The reaction of oxygen with the alkalizing steam ingredients is described. (orig.)

  2. The Wulf bands of oxygen

    Science.gov (United States)

    Bernath, Peter; Carleer, Michel; Fally, Sophie; Jenouvrier, Alain; Vandaele, Ann Carine; Hermans, Christian; Mérienne, Marie-France; Colin, Reginald

    1998-11-01

    The Wulf bands of oxygen in the 240-290 nm spectral region are caused by collision-induced absorption of the Herzberg III ( A' 3Δu- X3Σ-g) system. These bands had been previously attributed to the oxygen dimer, (O 2) 2. Under atmospheric conditions the Wulf bands are thus the long-wavelength extension of the Herzberg continuum. Absorption of solar radiation by the Wulf bands may be an additional source of NO in the stratosphere.

  3. 体外膜肺氧合联合持续肾脏替代治疗对健康小猪细胞因子表达的影响及意义%Effects of extracorporeal membrane oxygenation combined with continuous renal replacement treatment on cytokines in piglets

    Institute of Scientific and Technical Information of China (English)

    何长生; 虞文魁; 石佳靓; 陈启仪; 沈娟红; 胡益民; 殷红珍; 李宁; 黎介寿

    2013-01-01

    Objective Extracorporeal membrane oxygenation ( ECMO ) can reduce mortality in critically-ill patients, but almost all patients treated by ECMO develop a systemic inflammatory response syndrome ( SIRS ) characterized by a " cytokine storm" , leukocyte activation, and multisystem organ dysfunction. We investigated the effects of ECMO and its combination with continuous renal replacement treatment ( CRRT ) on the plasma concentrations of inflammatory cytokines in piglets. Methods We randomly divided 24 piglets into four groups of equal number: control, sham, ECMO, and ECMO + CRRT. We collected blood samples from the piglets 1 h before and 2,6, 12 and 24 h after treatment, and determined the plasma levels of TNF-ct, IL-1β, IL-6, IL-8 and IL-10 by ELISA. Results There were no significant differences in the plasma levels of the cytokines before treatment, nor in the control and sham groups after it. The levels of TNF-ct, IL-1β, IL-6 and IL-8 were increased after ECMO and ECMO + CRRT, more significantly after ECMO than after ECMO + CRRT ( P <0.05 ). However, the IL-10 concentration of the ECMO group first went up and then down, to the similar level of the control and sham groups at 24 h, and it rose, too, in the ECMO + CRRT group and maintained at a higher level though decreased a little at 12h, with statistically significant differences from the control group ( P < 0. 05 ) as well as from the ECMO group at 12 and 24 h ( P < 0.05 ). Conclusion ECMO can increase the release of proinflammation cytokines and attenuate anti-inflammatory cytokine, while its combination with CRRT can keep a balance between proinflammatory and anti-inflammatory cytokines in the body, and ameliorate ECMO related SIRS.%目的 体外膜肺氧合(extracorporeal membrane oxygenation,ECMO)治疗的患者均会发生不同程度的全身炎症反应,而持续肾脏替代治疗(continuous renal replacement treatment,CRRT)可以清除各种炎性递质,文中通过观察ECMO联合CRRT对健康小猪

  4. Oxygen and Early Animal Evolution

    Science.gov (United States)

    Xiao, S.

    2012-12-01

    It is often hypothesized that the rise of animals was triggered by an increase in O2 levels in the atmosphere and oceans. However, this hypothesis is remarkably difficult to test, because the timing of animal divergences is poorly resolved, the physiology of early animals is often unknown, estimates of past pO2 levels come with large error bars, and causal relationships between oxygenation and animal evolution are difficult to establish. Nonetheless, existing phylogenetic, paleontological, and geochemical data indicate that the evolution of macroscopic animals and motile macrometazoans with energetically expensive lifestyles may be temporally coupled with ocean oxygenation events in the Ediacaran Period. Thus, it is plausible that ocean oxygenation may have been a limiting factor in the early evolution of macroscopic, complex, and metabolically aggressive animals (particularly bilaterian animals). However, ocean oxygenation and animal evolution were likely engaged in two-way interactions: Ediacaran oxygenation may have initially lifted a physiological barrier for the evolution of animal size, motility, and active lifestyles, but subsequent animal diversification in the Paleozoic may have also changed oceanic redox structures. Viewed in a broader context, the early evolutionary history of animals was contingent upon a series of events, including genetic preparation (developmental genetics), environmental facilitation (oceanic oxygenation), and ecological escalation (Cambrian explosion), but the rise of animals to ecological importance also had important geobiological impacts on oceanic redox structures, sedimentary fabrics, and global geochemical cycles.

  5. Analgesic combinations

    Science.gov (United States)

    Raffa, Robert B.; Pergolizzi, Joseph V.; Tallarida, Ronald J.

    2010-01-01

    When the pathophysiology of a medical condition is multi-modal, i.e., related to multiple physiological causes or mediated by multiple pathways, the optimal strategy can be to use a drug or a combination of drugs that contribute multiple mechanisms to the therapeutic endpoint. In such situations, a rational multi-modal approach can also result in the fewest adverse effects. We discuss the quantitative analysis of multi-modal action using the treatment of pain as a practical example and give examples of its application to some widely used analgesic drugs. PMID:20338825

  6. Biogeochemical Modeling of the Second Rise of Oxygen

    Science.gov (United States)

    Smith, M. L.; Catling, D.; Claire, M.; Zahnle, K.

    2014-03-01

    The rise of atmospheric oxygen set the tempo for the evolution of complex life on Earth. Oxygen levels are thought to have increased in two broad steps: one step occurred in the Archean ~ 2.45 Ga (the Great Oxidation Event or GOE), and another step occured in the Neoproterozoic ~750-580 Ma (the Neoprotoerozoic Oxygenation Event or NOE). During the NOE, oxygen levels increased from ~1-10% of the present atmospheric level (PAL) (Holland, 2006), to ~15% PAL in the late Neoproterozoic, to ~100% PAL later in the Phanerozoic. Complex life requires O2, so this transition allowed complex life to evolve. We seek to understand what caused the NOE. To explore causes for the NOE, we build upon the biogeochemical model of Claire et al. (2006), which calculates the redox evolution of the atmosphere, ocean, biosphere, and crust in the Archean through to the early Proterozoic. In this model, the balance between oxygenconsuming and oyxgen-producing fluxes evolves over time such that at ~2.4 Ga, the rapidly acting sources of oxygen outweigh the rapidly-acting sinks. Or, in other words, at ~2.4 Ga, the flux of oxygen from organic carbon burial exceeds the sinks of oxygen from reaction with reduced volcanic and metamoprphic gases. The model is able to drive oxygen levels to 1-10% PAL in the Proterozoic; however, the evolving redox fluxes in the model cannot explain how oxygen levels pushed above 1-10% in the late Proterozoic. The authors suggest that perhaps another buffer, such as sulfur, is needed to describe Proterozoic and Phanerozoic redox evolution. Geologic proxies show that in the Proterozoic, up to 10% of the deep ocean may have been sulfidic. With this ocean chemistry, the global sulfur cycle would have worked differently than it does today. Because the sulfur and oxygen cycles interact, the oxygen concentration could have permanently changed due to an evolving sulfur cycle (in combination with evolving redox fluxes associated with other parts of the oxygen cycle and carbon

  7. EVALUATING AN INNOVATIVE OXYGEN SENSOR FOR REMOTE SUBSURFACE OXYGEN MEASUREMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Millings, M; Brian Riha, B; Warren Hyde, W; Karen Vangelas, K; Brian02 Looney, B

    2006-10-12

    Oxygen is a primary indicator of whether anaerobic reductive dechlorination and similar redox based processes contribute to natural attenuation remedies at chlorinated solvent contaminated sites. Thus, oxygen is a viable indicator parameter for documenting that a system is being sustained in an anaerobic condition. A team of researchers investigated the adaptation of an optical sensor that was developed for oceanographic applications. The optical sensor, because of its design and operating principle, has potential for extended deployment and sensitivity at the low oxygen levels relevant to natural attenuation. The results of the research indicate this tool will be useful for in situ long-term monitoring applications, but that the traditional characterization tools continue to be appropriate for characterization activities.

  8. Cardiogenic Shock: Failure of Oxygen Delivery and Oxygen Utilization.

    Science.gov (United States)

    Lim, Hoong Sern

    2016-08-01

    Cardiogenic shock remains a highly lethal condition. Conventional therapy including revascularization and mechanical circulatory support aims to improve cardiac output and oxygen delivery, but increasing basic and clinical observations indicate wider circulatory and cellular abnormalities, particularly at the advanced stages of shock. Progressive cardiogenic shock is associated with microcirculatory and cellular abnormalities. Cardiogenic shock is initially characterized by a failure to maintain global oxygen delivery; however, progressive cardiogenic shock is associated with the release of pro-inflammatory cytokines, derangement of the regulation of regional blood flow, microcirculatory abnormalities, and cellular dysoxia. These abnormalities are analogous to septic shock and may not be reversed by increase in oxygen delivery, even to supranormal levels. Earlier mechanical circulatory support in cardiogenic shock may limit the development of microcirculatory and cellular abnormalities.

  9. [Anesthesia and sedation by admixture of xenon-oxygen in dentistry. Part I].

    Science.gov (United States)

    Rabinovich, S A; Zavodilenko, L A; Babikov, A S

    2014-01-01

    The modern out-patient dental treatment which is performed under combined anesthesia with of xenon-oxygen inhalations provides comfortable conditions for the doctor and the patient, effective anesthesia and safe level of the sedation controlled by dentist.

  10. COMPARISON OF METHODS TO DETERMINE OXYGEN DEMAND FOR BIOREMEDIATION OF A FUEL CONTAMINATED AQUIFER

    Science.gov (United States)

    Four analytical methods were compared for estimating concentrations of fuel contaminants in subsurface core samples. The methods were total organic carbon, chemical oxygen demand, oil and grease, and a solvent extraction of fuel hydrocarbons combined with a gas chromatographic te...

  11. Oxygen-Partial-Pressure Sensor for Aircraft Oxygen Mask

    Science.gov (United States)

    Kelly, Mark; Pettit, Donald

    2003-01-01

    A device that generates an alarm when the partial pressure of oxygen decreases to less than a preset level has been developed to help prevent hypoxia in a pilot or other crewmember of a military or other high-performance aircraft. Loss of oxygen partial pressure can be caused by poor fit of the mask or failure of a hose or other component of an oxygen distribution system. The deleterious physical and mental effects of hypoxia cause the loss of a military aircraft and crew every few years. The device is installed in the crewmember s oxygen mask and is powered via communication wiring already present in all such oxygen masks. The device (see figure) includes an electrochemical sensor, the output potential of which is proportional to the partial pressure of oxygen. The output of the sensor is amplified and fed to the input of a comparator circuit. A reference potential that corresponds to the amplified sensor output at the alarm oxygen-partial-pressure level is fed to the second input of the comparator. When the sensed partial pressure of oxygen falls below the minimum acceptable level, the output of the comparator goes from the low state (a few millivolts) to the high state (near the supply potential, which is typically 6.8 V for microphone power). The switching of the comparator output to the high state triggers a tactile alarm in the form of a vibration in the mask, generated by a small 1.3-Vdc pager motor spinning an eccentric mass at a rate between 8,000 and 10,000 rpm. The sensation of the mask vibrating against the crewmember s nose is very effective at alerting the crewmember, who may already be groggy from hypoxia and is immersed in an environment that is saturated with visual cues and sounds. Indeed, the sensation is one of rudeness, but such rudeness could be what is needed to stimulate the crewmember to take corrective action in a life-threatening situation.

  12. Low oxygen biomass-derived pyrolysis oils and methods for producing the same

    Science.gov (United States)

    Marinangeli, Richard; Brandvold, Timothy A; Kocal, Joseph A

    2013-08-27

    Low oxygen biomass-derived pyrolysis oils and methods for producing them from carbonaceous biomass feedstock are provided. The carbonaceous biomass feedstock is pyrolyzed in the presence of a catalyst comprising base metal-based catalysts, noble metal-based catalysts, treated zeolitic catalysts, or combinations thereof to produce pyrolysis gases. During pyrolysis, the catalyst catalyzes a deoxygenation reaction whereby at least a portion of the oxygenated hydrocarbons in the pyrolysis gases are converted into hydrocarbons. The oxygen is removed as carbon oxides and water. A condensable portion (the vapors) of the pyrolysis gases is condensed to low oxygen biomass-derived pyrolysis oil.

  13. 21 CFR 868.5580 - Oxygen mask.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Oxygen mask. 868.5580 Section 868.5580 Food and... ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5580 Oxygen mask. (a) Identification. An oxygen mask is a device placed over a patient's nose, mouth, or tracheostomy to administer oxygen or aerosols. (b)...

  14. A Theory of Atmospheric Oxygen

    OpenAIRE

    2015-01-01

    There is no direct geologic record of the level of free oxygen in the atmosphere over Earth history. Indirect proxy records have led to a canonical view of atmospheric pO2, according to which the atmosphere has passed through three stages. During the first of these periods, corresponding roughly to the Archean eon, pO2 was less than 0.001% present atmospheric levels (PAL). Oxygen levels rose abruptly around 2.4 billion years ago, a transition referred to as the “Great Oxidation Event” (GOE...

  15. High Temperature Sorbents for Oxygen

    Science.gov (United States)

    Sharma, Pramod K. (Inventor)

    1996-01-01

    A sorbent capable of removing trace amounts of oxygen (ppt) from a gas stream at a high temperature above 200 C is introduced. The sorbent comprises a porous alumina silicate support such as zeolite containing from 1 to 10 percent by weight of ion exchanged transition metal such as copper or cobalt ions and 0.05 to 1.0 percent by weight of an activator selected from a platinum group metal such as platinum. The activation temperature, oxygen sorption and reducibility are all improved by the presence of the platinum activator.

  16. Volatile hydrocarbons and fuel oxygenates: Chapter 12

    Science.gov (United States)

    Cozzarelli, Isabelle M.

    2014-01-01

    Petroleum hydrocarbons and fuel oxygenates are among the most commonly occurring and widely distributed contaminants in the environment. This chapter presents a summary of the sources, transport, fate, and remediation of volatile fuel hydrocarbons and fuel additives in the environment. Much research has focused on the transport and transformation processes of petroleum hydrocarbons and fuel oxygenates, such as benzene, toluene, ethylbenzene, and xylenes and methyl tert‐butyl ether, in groundwater following release from underground storage tanks. Natural attenuation from biodegradation limits the movement of these contaminants and has received considerable attention as an environmental restoration option. This chapter summarizes approaches to environmental restoration, including those that rely on natural attenuation, and also engineered or enhanced remediation. Researchers are increasingly combining several microbial and molecular-based methods to give a complete picture of biodegradation potential and occurrence at contaminated field sites. New insights into the fate of petroleum hydrocarbons and fuel additives have been gained by recent advances in analytical tools and approaches, including stable isotope fractionation, analysis of metabolic intermediates, and direct microbial evidence. However, development of long-term detailed monitoring programs is required to further develop conceptual models of natural attenuation and increase our understanding of the behavior of contaminant mixtures in the subsurface.

  17. Nanomaterial-based robust oxygen sensor

    Science.gov (United States)

    Goswami, Kisholoy; Sampathkumaran, Uma; Alam, Maksudul; Tseng, Derek; Majumdar, Arun K.; Kazemi, Alex A.

    2007-09-01

    Since the TWA flight 800 accident in July 1996, significant emphasis has been placed on fuel tank safety. The Federal Aviation Administration (FAA) has focused research to support two primary methods of fuel tank protection - ground-based and on-board - both involving fuel tank inerting. Ground-based fuel tank inerting involves some combination of fuel scrubbing and ullage washing with Nitrogen Enriched Air (NEA) while the airplane is on the ground (applicable to all or most operating transport airplanes). On-board fuel tank inerting involves ullage washing with OBIGGS (on-board inert gas generating system), a system that generates NEA during aircraft operations. An OBIGGS generally encompasses an air separation module (ASM) to generate NEA, a compressor, storage tanks, and a distribution system. Essential to the utilization of OBIGGS is an oxygen sensor that can operate inside the aircraft's ullage and assess the effectiveness of the inerting systems. OBIGGS can function economically by precisely knowing when to start and when to stop. Toward achieving these goals, InnoSense LLC is developing an all-optical fuel tank ullage sensor (FTUS) prototype for detecting oxygen in the ullage of an aircraft fuel tank in flight conditions. Data would be presented to show response time and wide dynamic range of the sensor in simulated flight conditions and fuel tank environment.

  18. Effect of dissolved oxygen in alcoholic beverages and drinking water on alcohol elimination in humans.

    Science.gov (United States)

    Rhee, Su-jin; Chae, Jung-woo; Song, Byung-jeong; Lee, Eun-sil; Kwon, Kwang-il

    2013-02-01

    Oxygen plays an important role in the metabolism of alcohol. An increased dissolved oxygen level in alcoholic beverages reportedly accelerates the elimination of alcohol. Therefore, we evaluated the effect of dissolved oxygen in alcohol and the supportive effect of oxygenated water on alcohol pharmacokinetics after the excessive consumption of alcohol, i.e., 540 ml of 19.5% alcohol (v/v). Fifteen healthy males were included in this randomized, 3 × 3 crossover study. Three combinations were tested: X, normal alcoholic beverage and normal water; Y, oxygenated alcoholic beverage and normal water; Z, oxygenated alcoholic beverage and oxygenated water. Blood alcohol concentrations (BACs) were determined by conversion of breath alcohol concentrations. Four pharmacokinetic parameters (C(max), T(max), K(el), and AUCall) were obtained using non-compartmental analysis and the times to reach 0.05% and 0.03% BAC (T(0.05%) and T(0.03%)) were compared using one-way analysis of variance (ANOVA) and Duncan's post hoc test. With combination Z, the BAC decreased to 0.05% significantly faster (p water augments the effect of oxygen in the alcoholic beverage in alcohol elimination. Therefore, it is necessary to investigate the supportive effect of ingesting additional oxygenated water after heavy drinking of normal alcoholic beverages.

  19. Nanoparticulate-catalyzed oxygen transfer processes

    Science.gov (United States)

    Hunt, Andrew T.; Breitkopf, Richard C.

    2009-12-01

    Nanoparticulates of oxygen transfer materials that are oxides of rare earth metals, combinations of rare earth metals, and combinations of transition metals and rare earth metals are used as catalysts in a variety of processes. Unexpectedly large thermal efficiencies are achieved relative to micron sized particulates. Processes that use these catalysts are exemplified in a multistage reactor. The exemplified reactor cracks C6 to C20 hydrocarbons, desulfurizes the hydrocarbon stream and reforms the hydrocarbons in the stream to produce hydrogen. In a first reactor stage the steam and hydrocarbon are passed through particulate mixed rare earth metal oxide to crack larger hydrocarbon molecules. In a second stage, the steam and hydrocarbon are passed through particulate material that desulfurizes the hydrocarbon. In a third stage, the hydrocarbon and steam are passed through a heated, mixed transition metal/rare earth metal oxide to reform the lower hydrocarbons and thereby produce hydrogen. Stages can be alone or combined. Parallel reactors can provide continuous reactant flow. Each of the processes can be carried out individually.

  20. Electrochemical determination of oxygen stoichiometry and entropy in oxides

    DEFF Research Database (Denmark)

    Zachau-Christiansen, Birgit; Jacobsen, Torben; Skaarup, Steen

    1996-01-01

    The oxygen stoichiometry of CeO2 and Ce0.82Gd0.18O1.91 is determined by a combination of cyclic voltammetry and coulometric titration. The electrochemical cell employed is an oxygen pumping cell, in which the oxide is subjected to different oxygen pressures corresponding to the potential imposed...... in the temperature range 800-1000 degrees C. With scan rates of 2 mu V/s potential sweeps on CeO2 are reversible. The change in entropy is determined by either subtraction of e.m.f. curves obtained by potential sweeps of different temperatures or by measuring the e.m.f. during a temperature scan. The latter method...

  1. Universality in Oxygen Evolution Electrocatalysis on Oxide Surfaces

    DEFF Research Database (Denmark)

    Man, Isabela Costinela; Su, Hai-Yan; Vallejo, Federico Calle

    2011-01-01

    with the computational standard hydrogen electrode (SHE) model. We showed that by the discovery of a universal scaling relation between the adsorption energies of HOO* vs HO*, it is possible to analyze the reaction free energy diagrams of all the oxides in a general way. This gave rise to an activity volcano......Trends in electrocatalytic activity of the oxygen evolution reaction (OER) are investigated on the basis of a large database of HO* and HOO* adsorption energies on oxide surfaces. The theoretical overpotential was calculated by applying standard density functional theory in combination...... that was the same for a wide variety of oxide catalyst materials and a universal descriptor for the oxygen evolution activity, which suggests a fundamental limitation on the maximum oxygen evolution activity of planar oxide catalysts....

  2. Effects of hyperbaric oxygen combined with acupuncture and low-dose L-dopa on the improvement of life quality of the patients with Parkinson's disease%高压氧、针灸联合小剂量美多巴改善帕金森综合征患者生活质量的临床研究

    Institute of Scientific and Technical Information of China (English)

    闫各; 崔倩倩; 孔敏

    2015-01-01

    Objective To investigate the effects of hyperbaric oxygen ( HBO ) combined with acupuncture and low-dose L-dopa on the improvement of motor and non-motor symptoms and life quality of the patients with Parkinson's disease.Methods One hundred and forty PD patients were chosen for our study . With the knowledge and consent of the patients and their dependents , the patients were divided into 4 groups, by different treatment methods:group A (the acupuncture plus small-dose L-dopa group, n=20 cases), group B ( the HBO plus small-dose L-dopa group , n=20 cases ) , group C ( the HBO plus acupuncture and plus small-dose L-dopa group , n =60 cases ) , and group D ( the small-dose L-dopa group , n =40 cases ) . Improvement of motor and non-motor symptoms and their life quality of the patients were assessed by using the EQ-5D, Uniform Parkinson's Disease Rating Scale (UPDRS), Hoehn-Yahr (H-Y) Rating Scale, Parkinson's Disease Sleep Scale ( PDSS) , Hamilton Anxiety Rating Scale ( HAMA) and Hamilton Depression Rating Scale (HAMD).Results (1)After one month of treatment, the scores of UPDRS I, UPDRS II and UPDRSⅢfor group A were respectively 7.71, 6.14 and 6.50, the scores for group B were respectively 6.87, 6.09 and 6.66, the scores for group C were respectively 6.69, 6.66 and 9.68, and the scores for group D were respectively 7.79, 6.07 and 6.41.The scores of HAMA, HAMD, PDSS and EQ-5D were significantly improved as compared with those before treatment (P<0.05), indicating that the 4 treatment profiles within a relatively short time could all improve the motor and non-motor symptoms and life quality of the PD patients The scores of UPDRSⅢ, HAMA, HAMD and PDSS for group C were more significantly improved (P<0.05).(2) After 6 months of prolonged treatment , statistical significance could be noted in the scores of UPDRS Ⅲ, HAMA, HAMD and PDSS in the patients of group C (P <0.05).(3) Following 6 months of prolonged treatment , the life quality of the patients in group C

  3. Transient electromagnetic behaviour in inductive oxygen and argon-oxygen plasmas

    Science.gov (United States)

    Chadwick, A. R.; Herdrich, G.; Kim, M.; Dally, B.

    2016-12-01

    In order to develop inductive electric propulsion as a flexible, throttleable technology for future space operations, a greater understanding of discharge transitions within the inductive plasma generator discharge chamber is required. This paper presents a non-intrusive method to determine the conditions under which transitions between the capacitive, low inductive, and high inductive regimes occur with greater accuracy, as well as determining the proportion of a single discharge cycle the plasma spends in either capacitive or inductive regime. Such a method allows a more robust method of classification of inductive discharges than previously available and can be applied to numerous gases. This approach presents an advantage over previous methods which relied on strongly radiating or thermally reactive gases to exhibit certain behaviour (due to the restriction of classical diagnostics on such high power sources) before a transition could be confirmed. This paper presents results from the proposed method applied to a pure oxygen plasma as well as two combinations of argon and oxygen (at 1:1 and 3:2 Ar:O2 volumetric ratios) in order to assess the tunability of electromagnetic regime transitions through modifications of gas composition rather than mechanical alterations. Transitions to the higher inductive mode were observed for much lower input powers for the argon-oxygen blends, as was expected, allowing final discharge conditions to occupy the inductive regime for 94% and 85% of a single discharge cycle for the 3:2 and 1:1 Ar:O2 mixtures, respectively. Pure oxygen achieved a maximum inductive proportion of 71% by comparison.

  4. Type of mask may impact on continuous positive airway pressure adherence in apneic patients.

    Directory of Open Access Journals (Sweden)

    Jean Christian Borel

    Full Text Available RATIONALE: In obstructive sleep apnea patients (OSA, continuous positive airway pressure (CPAP adherence is crucial to improve symptoms and cardiometabolic outcomes. The choice of mask may influence CPAP adherence but this issue has never been addressed properly. OBJECTIVE: To evaluate the impact of nasal pillows, nasal and oronasal masks on CPAP adherence in a cohort of OSA. METHODS: Newly CPAP treated OSA participating in "Observatoire Sommeil de la Fédération de Pneumologie", a French national prospective cohort, were included between March 2009 and December 2011. Anthropometric data, medical history, OSA severity, sleepiness, depressive status, treatment modalities (auto-CPAP versus fixed pressure, pressure level, interface type, use of humidifiers and CPAP-related side effects were included in multivariate analysis to determine independent variables associated with CPAP adherence. RESULTS: 2311 OSA (age = 57(12 years, apnea+hypopnea index = 41(21/h, 29% female were included. Nasal masks, oronasal masks and nasal pillows were used by 62.4, 26.2 and 11.4% of the patients, respectively. In univariate analysis, oronasal masks and nasal pillows were associated with higher risk of CPAP non-adherence. CPAP non-adherence was also associated with younger age, female gender, mild OSA, gastroesophageal reflux, depression status, low effective pressure and CPAP-related side effects. In multivariate analysis, CPAP non-adherence was associated with the use of oronasal masks (OR = 2.0; 95%CI = 1.6; 2.5, depression, low effective pressure, and side effects. CONCLUSION: As oronasal masks negatively impact on CPAP adherence, a nasal mask should be preferred as the first option. Patients on oronasal masks should be carefully followed.

  5. Effects of hyperbaric oxygen combined with reinhartdt and sea cumber capsule therapy on abilities of learning and memory in vascular dementia rats%高压氧联合复方海蛇胶囊对血管性痴呆大鼠学习记忆能力行为学的影响

    Institute of Scientific and Technical Information of China (English)

    朱燕平; 寇雪莲; 何松彬; 唐维国

    2013-01-01

    Objective:To investigate the effect's of hyperbaric oxygen(HBO) combined with reinhartdt and sea cumber capsule (RSC) therapy on abilities of learning and memory in vascular dementia rats.Method: In forty Sprague-Dawly rats weighted 250—300g, the reperfusion middle cerebral artery occlusion (rM-CAO) models were established with thread embolism method. These model rats were divided into five groups: sham-operated(SHAM) group, MCAO mode(MCAO), HBO treatment(HBO) group, reinhartdt and sea cumber capsule treatment(RSC) group and HBO combined with RSC treatment(HBO + RSC) group, 8 rats in each group. At the end of 4 week treatment with HBO and/or RSC, the abilities of learning and memory of rats were assessed with Morris water maze. Result: ①In Morris water maze test, the average escape latencies in HBO group(41.15 ± 6.75s),RSC group(44.11± 6.05s) and HBO+RSC group(29.32 ± 3.72s) were significantly shorter than that in MCAO group(67.05 ± 9.00s) (P0.05). ② The average swimming path lengths in HBO group(7631.89 ± 1277.73mm),RSC group(8114.48 ± 1091.82mm)anrl HBO+RSC group (5699.27 ± 1339.82mm) were significantly shorter than that in MCAO group(12492.46 ± 2161.74mm) (P0.05). ③The striding platform times in HBO group(2.74 ± 0.65 times),RSC group(2.25 ± 0.87 times) and HBO+ RSC(3.82 ± 0.96 times) were significantly longer than that in MCAO group(1.06 ± 0.55 times) (P0.05).④The platform detention time in HBO group (30.05 ± 3.58s),RSC group(30.24± 5.13s) and HBO + RSC group(35.29 ± 3.51s) increased significantly than that in MCAO group (24.52 ± 4.05s)(P<0.05); the platform detention time in HBO+RSC group increased significantly than that in HBO group or RSC group(P<0.05); no significant difference was found between RSC group and HBO group. Conclusion: HBO and/or RSC therapy could improve learning and memory abilities in vascular dementia rats effectively. The effect of HBO combined with RSC therapy in vascular dementia rats was much better than either

  6. Measuring Spatial and Temporal Heterogeneity of Dissolved Oxygen in Streambed Sediments Using Pressure Sensitive Paint (PSP)

    Science.gov (United States)

    Huynh, K. T.; Salus, A.; Xie, M.; Roche, K. R.; Packman, A. I.

    2014-12-01

    Pressure sensitive paints (PSP) have been largely used in aerodynamic applications to measure pressure distributions on complex bodies such as aircraft. One common family of PSPs employ fluorescent pigments that are quenched in the presence of oxygen, yielding an inverse relationship between fluorescence intensity and oxygen concentration that is used to measure pressure in aerodynamic applications through the partial pressure of oxygen. These PSPs offer unexplored potential for visualizing dissolved oxygen (DO) concentration distributions on surfaces underwater. PSP was used to measure dissolved oxygen concentrations in streambed sediments in a laboratory flume. Two PSP-coated 2.5 cm diameter spheres were emplaced in a bed of similar material, and imaged under varying DO concentrations. Calibration curves relating fluorescence intensity to dissolved oxygen concentration were developed on a pixel-by-pixel basis, enabling spatial patterns of oxygen to be resolved in the sediment bed. This method of measuring dissolved oxygen concentration is advantageous because of its fast response time and ability to measure heterogeneous oxygen distributions in sediments. Future work will explore the combined effects of stream flow and biofilm growth on oxygen distributions in streambed sediments.

  7. Diffusion of oxygen in cork.

    Science.gov (United States)

    Lequin, Sonia; Chassagne, David; Karbowiak, Thomas; Simon, Jean-Marc; Paulin, Christian; Bellat, Jean-Pierre

    2012-04-01

    This work reports measurements of effective oxygen diffusion coefficient in raw cork. Kinetics of oxygen transfer through cork is studied at 298 K thanks to a homemade manometric device composed of two gas compartments separated by a cork wafer sample. The first compartment contains oxygen, whereas the second one is kept under dynamic vacuum. The pressure decrease in the first compartment is recorded as a function of time. The effective diffusion coefficient D(eff) is obtained by applying Fick's law to transient state using a numerical method based on finite differences. An analytical model derived from Fick's law applied to steady state is also proposed. Results given by these two methods are in close agreement with each other. The harmonic average of the effective diffusion coefficients obtained from the distribution of 15 cork wafers of 3 mm thickness is 1.1 × 10(-9) m(2) s(-1) with a large distribution over four decades. The statistical analysis of the Gaussian distribution obtained on a 3 mm cork wafer is extrapolated to a 48 mm cork wafer, which length corresponds to a full cork stopper. In this case, the probability density distribution gives a mean value of D(eff) equal to 1.6 × 10(-9) m(2) s(-1). This result shows that it is possible to obtain the effective diffusion coefficient of oxygen through cork from short time (few days) measurements performed on a thin cork wafer, whereas months are required to obtain the diffusion coefficient for a full cork stopper. Permeability and oxygen transfer rate are also calculated for comparison with data from other studies.

  8. Image-based modelling of skeletal muscle oxygenation.

    Science.gov (United States)

    Zeller-Plumhoff, B; Roose, T; Clough, G F; Schneider, P

    2017-02-01

    The supply of oxygen in sufficient quantity is vital for the correct functioning of all organs in the human body, in particular for skeletal muscle during exercise. Disease is often associated with both an inhibition of the microvascular supply capability and is thought to relate to changes in the structure of blood vessel networks. Different methods exist to investigate the influence of the microvascular structure on tissue oxygenation, varying over a range of application areas, i.e. biological in vivo and in vitro experiments, imaging and mathematical modelling. Ideally, all of these methods should be combined within the same framework in order to fully understand the processes involved. This review discusses the mathematical models of skeletal muscle oxygenation currently available that are based upon images taken of the muscle microvasculature in vivo and ex vivo Imaging systems suitable for capturing the blood vessel networks are discussed and respective contrasting methods presented. The review further informs the association between anatomical characteristics in health and disease. With this review we give the reader a tool to understand and establish the workflow of developing an image-based model of skeletal muscle oxygenation. Finally, we give an outlook for improvements needed for measurements and imaging techniques to adequately investigate the microvascular capability for oxygen exchange.

  9. The initial interactions of oxygen with polycrystalline titanium surfaces

    Science.gov (United States)

    Azoulay, A.; Shamir, N.; Fromm, E.; Mintz, M. H.

    1997-01-01

    The interactions of gaseous oxygen and different types of polycrystalline titanium surfaces were studied at room temperature within the exposure range of 0-1000 L. Combined measurements utilizing direct recoils spectrometry (DRS), Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), and work function variations enabled the distinction between processes occurring on the topmost atomic layer and those associated with subsurface incorporation of oxygen. Also, the different chemical forms (oxidation states) developing during the exposure course were identified. The results were compared for three types of surfaces, each prepared by a different cleaning procedure. It has been concluded that: (i) Oxygen initially accumulates on the topmost atomic layer, regardless of the type of the studied surface. No preferred subsurface occupation has been observed. (ii) The kinetics of initial accumulation (up to a complete surface coverage) are similar for all the different types of surfaces. (iii) Mixtures of different oxidation states of titanium (0, +2, +3, +4) are present during the whole course of exposure. Qualitatively, increasing proportions of the higher valence states are displayed for higher oxygen exposures. However, the quantitative estimates of their relative amounts indicate a strong dependence on the type of surface, with preferred high oxidation (+4) states obtained for high temperature annealed samples (as compared with room temperature sputtered surfaces). (iv) Topmost oxygen atoms which terminate the oxides surfaces are less negatively charged than the underlying (i.e., subsurface) "oxidic" atoms. These results may account for some of the controversies presented in the literature.

  10. Oxygen supply and consumption in soilless culture: evaluation of an oxygen simulation model for cucumber

    NARCIS (Netherlands)

    Baas, R.; Wever, G.; Koolen, A.J.; Tariku, E.; Stol, K.J.

    2001-01-01

    A soil oxygen simulation model (OXSI) was tested and evaluated for evaluating growing media with respect to aeration. In the model, local oxygen concentrations are calculated from coefficients of diffusion and consumption (respiration), assuming equilibrium conditions. Apparent oxygen diffusion coef

  11. Synthesis gas production using oxygen storage materials as oxygen carrier over circulating fluidized bed

    Institute of Scientific and Technical Information of China (English)

    DAI Xiaoping; YU Changchun; LI Ranjia; WU Qiong; HAO Zhengping

    2008-01-01

    A novel process for synthesis gas production over Circulating Fluidized Bed (CFB) using oxygen storage materials as oxygen carrier was reported. First, oxygen in the air was chemically fixed and converted to lattice oxygen of oxygen storage materials over regenerator, and then methane was selectively oxidized to synthesis gas with lattice oxygen of oxygen storage materials over riser reactor. The results from simulation reaction of CFB by sequential redox reaction on a fixed bed reactor using lanthanum-based perovskite LaFeO3 and La0.8Sr0.2Fe0.9Co0.1O3 oxides prepared by sol-gel, suggested that the depleted oxygen species could be regenerated, and methane could be oxidized to synthesis gas by lattice oxygen with high selectivity. The partial oxidation of methane to synthesis gas over CFB using lattice oxygen of the oxygen storage materials instead of gaseous oxygen should be possibly applicable.

  12. Efficacy comparison of oral steroid, intratympanic steroid, hyperbaric oxygen and oral steroid + hyperbaric oxygen treatments in idiopathic sudden sensorineural hearing loss cases.

    Science.gov (United States)

    Alimoglu, Yalcin; Inci, Ender; Edizer, Deniz Tuna; Ozdilek, Alper; Aslan, Mehmet

    2011-12-01

    Idiopathic sudden sensorineural hearing loss is a rare disorder of unknown pathogenesis in which hearing is lost partially or totally. About 60 treatment modalities have been described. We aimed to compare the efficacy of hyperbaric oxygen, oral steroid, intratympanic steroid therapy and their combinations in idiopathic sudden sensorineural hearing loss patients. Files of patients who were followed up between 2004 and 2010 in our clinic were examined retrospectively. Patients were divided into four groups according to the therapy received: Oral steroid, oral steroid + hyperbaric oxygen, intratympanic steroid and hyperbaric oxygen. Treatment success was assessed by Siegel criteria and mean gains using pre-treatment and post-treatment audiograms. 217 patients and 219 ears were examined. The proportion of patients responding to therapy was the highest in the oral steroid + hyperbaric oxygen group with 86.88% (53/61) followed by the oral steroid group with 63.79% (37/58), the intratympanic steroid group with 46,51% (20/43) and the hyperbaric oxygen group with 43.85% (25/57). The proportion of patients who had complete recovery was the highest in the oral steroid + hyperbaric oxygen group with 42.6% (26/61) followed by the oral steroid group with 19.0% (11/58), the hyperbaric oxygen group with 17.5% (10/57) and the intratympanic steroid group with 11.6% (5/43). The oral steroid + hyperbaric oxygen group has the highest mean hearing gain among all groups (p sudden sensorineural hearing loss patients receiving oral steroid + hyperbaric oxygen combination therapy have a higher likelihood of recovery than patients receiving oral steroids, hyperbaric oxygen or intratympanic steroids alone.

  13. Diurnal fluctuations in root oxygen release rate and dissolved oxygen budget in wetland mesocosm

    OpenAIRE

    Dong, C.; Zhu, W; Zhao, Y. Q.; Gao, M

    2011-01-01

    To assess the role of plants for oxygen offering in constructed wetlands, this study experimentally evaluated the amount of root oxygen release rate using mass balance method. The mass balance calculation is based on the following components: respiratory oxygen consumption of the roots; oxygen required for degradation of the organic matters; oxygen required for nitrification; and the amount of dissolved oxygen in the influent, effluent and substrate water. Experimental results have demonstrat...

  14. Investigation of Oxygen Vacancy and Interstitial Oxygen Defects in ZnO Films by Photoluminescence and X-Ray Photoelectron Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    FAN Hai-Bo; YANG Shao-Yan; ZHANG Pan-Feng; WEI Hong-Yuan; LIU Xiang-Lin; JIAO Chun-Mei; ZHU Qin-Sheng; CHEN Yong-Hai; WANG Zhan-Guo

    2007-01-01

    ZnO films prepared at different temperatures and annealed at 900 C in oxygen are studied by photoluminescence (PL) and x-ray photoelectron spectroscopy (XPS). It is observed that in the PL of the as-grown films the green luminescence (GL) and the yellow luminescence (YL) are related, and after annealing the GL is restrained and the YL is enhanced. The O 1s XPS results also show the coexistence of oxygen vacancy (Vo) and interstitial oxygen (Oi) before annealing and the quenching of the Vo after annealing. By combining the two results it is deduced that the GL and YL are related to the Vo and Oi defects, respectively.

  15. Oxygen Tension Within the Neurogenic Niche Regulates Dopaminergic Neurogenesis in the Developing Midbrain

    Science.gov (United States)

    Wagenführ, Lisa; Meyer, Anne Karen; Marrone, Lara

    2016-01-01

    Oxygen tension is an important factor controlling stem cell proliferation and maintenance in various stem cell populations with a particular relevance in midbrain dopaminergic progenitors. Further studies have shown that the oxygen-dependent transcription factor hypoxia-inducible factor 1α (HIF-1α) is involved in these processes. However, all available studies on oxygen effects in dopaminergic neuroprogenitors were performed in vitro and thus it remains unclear whether tissue oxygen tension in the embryonic midbrain is also relevant for the regulation of dopaminergic neurogenesis in vivo. We thus dissect here the effects of oxygen tension in combination with HIF-1α conditional knockout on dopaminergic neurogenesis by using a novel experimental design allowing for the control of oxygen tension within the microenvironment of the neurogenic niche of the murine fetal midbrain in vivo. The microenvironment of the midbrain dopaminergic neurogenic niche was detected as hypoxic with oxygen tensions below 1.1%. Maternal oxygen treatment of 10%, 21%, and 75% atmospheric oxygen tension for 48 h translates into robust changes in fetal midbrain oxygenation. Fetal midbrain hypoxia hampered the generation of dopaminergic neurons and is accompanied with restricted fetal midbrain development. In contrast, induced hyperoxia stimulated proliferation and differentiation of dopaminergic progenitors during early and late embryogenesis. Oxygen effects were not directly mediated through HIF-1α signaling. These data—in agreement with in vitro data—indicate that oxygen is a crucial regulator of developmental dopaminergic neurogenesis. Our study provides the initial framework for future studies on molecular mechanisms mediating oxygen regulation of dopaminergic neurogenesis within the fetal midbrain as its natural environment. PMID:26577812

  16. Evaluation of different oxygen, carbon dioxide and nitrogen combinations employed to extend the shelf life of fresh-cut collard greens Avaliação de diferentes combinações de oxigênio, gás carbônico e nitrogênio utilizadas no aumento de vida de prateleira de couve minimamente processada

    Directory of Open Access Journals (Sweden)

    Celso L. Moretti

    2003-12-01

    Full Text Available Collard greens (Brassica oleracea var. acephala "Manteiga" were harvested in commercial fields in Brasilia, Brazil, aiming to evaluate different oxygen, carbon dioxide and nitrogen combinations to extend the shelf life of the fresh-cut product. After harvest, leaves were taken to the postharvest laboratory, selected for external blemishes and minimally processed (3 mm thick inside a cold room (13±2°C. After processing, fresh-cut collard greens were stored under two controlled atmosphere (CA conditions (3% O2, 4% CO2; 5% O2, 5% CO2/balance N2, and normal air (control, at 5°C (95±2% RH, for six days. Daily, minimally processed collard greens were evaluated for total vitamin C, total chlorophyll, total soluble solids content, and titratable acidity. Total vitamin C content decreased for all treatments during the storage period. Storage under CA conditions delayed total vitamin C degradation for both atmospheres studied. At the end of the storage period, fresh-cut collard greens stored under 3% O2, 4% CO2 showed around 25% and 56% more vitamin C than the material stored under 5% O2, 5% CO2 and control, respectively. Total chlorophyll content decreased during the storage period. At the end of the experiment, fresh-cut collard greens stored under 3% O2, 4% CO2 showed 24% and 45% more total chlorophyll than the product stored under 5% O2, 5% CO2 and control, respectively. CA storage delayed organic acid degradation. On the sixth day, fresh-cut collard greens stored under 3% O2, 4% CO2 presented around 44% more organic acids than control. Total soluble solids content were not significantly affected.Folhas de couve (Brassica oleracea var. acephala "Manteiga" foram obtidas em campos de produção comercial em Brasília, DF, com o objetivo de avaliar diferentes combinações de oxigênio, dióxido de carbono e nitrogênio para estender a vida de prateleira do produto minimamente processado. Após colhidas, as folhas foram levadas ao laboratório de p

  17. Oxygen permeation and thermo-chemical stability of oxygen separation membrane materials for the oxyfuel process

    Energy Technology Data Exchange (ETDEWEB)

    Ellett, Anna Judith

    2009-07-01

    The reduction of CO{sub 2} emissions, generally held to be one of the most significant contributors to global warming, is a major technological issue. CO{sub 2} Capture and Storage (CCS) techniques applied to large stationary sources such as coal-fired power plants could efficiently contribute to the global carbon mitigation effort. The oxyfuel process, which consists in the burning of coal in an oxygen-rich atmosphere to produce a flue gas highly concentrated in CO{sub 2}, is a technology considered for zero CO{sub 2} emission coal-fired power plants. The production of this O{sub 2}-rich combustion gas from air can be carried out using high purity oxygen separation membranes. Some of the most promising materials for this application are mixed ionic-electronic conducting (MIEC) materials with perovskite and K{sub 2}NiF{sub 4} perovskite-related structures. The present work examines the selection of La{sub 0.58}Sr{sub 0.4}Co{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} (LSCF58), La{sub 2}NiO{sub 4+{delta}}, Pr{sub 0.58}Sr{sub 0.4}Co{sub 0.2}Fe{sub 0.8}O{sub 3-{delta}} (PSCF58) and Ba{sub 0.5}Sr{sub 0.5}Co{sub 0.8}Fe{sub 0.2}O{sub 3-{delta}} (BSCF50) as membrane materials for the separation of O{sub 2} and N{sub 2} in the framework of the oxyfuel process with flue gas recycling. Annealing experiments were carried out on pellets exposed to CO{sub 2}, water vapour, O{sub 2} and Cr{sub 2}O{sub 3} in order to determine the thermo-chemical resistance to the atmospheres and the high temperature conditions present during membrane operation in a coal-fired power plant. The degradation of their microstructure was investigated using Scanning Electron Microscopy (SEM) in combination with electron dispersive spectroscopy (EDS) as well as X-Ray Diffraction (XRD). Also, the oxygen permeation fluxes of selected membranes were investigated as a function of temperature. The membrane materials selected were characterised using thermo-analytical techniques such as precision thermogravimetric

  18. Ammonium excretion and oxygen respiration of tropical copepods and euphausiids exposed to oxygen minimum zone conditions

    Science.gov (United States)

    Kiko, Rainer; Hauss, Helena; Buchholz, Friedrich; Melzner, Frank

    2016-04-01

    Calanoid copepods and euphausiids are key components of marine zooplankton communities worldwide. Most euphausiids and several copepod species perform diel vertical migrations (DVMs) that contribute to the export of particulate and dissolved matter to midwater depths. In vast areas of the global ocean, and in particular in the eastern tropical Atlantic and Pacific, the daytime distribution depth of many migrating organisms corresponds to the core of the oxygen minimum zone (OMZ). At depth, the animals experience reduced temperature and oxygen partial pressure (pO2) and an increased carbon dioxide partial pressure (pCO2) compared to their near-surface nighttime habitat. Although it is well known that low oxygen levels can inhibit respiratory activity, the respiration response of tropical copepods and euphausiids to relevant pCO2, pO2, and temperature conditions remains poorly parameterized. Further, the regulation of ammonium excretion at OMZ conditions is generally not well understood. It was recently estimated that DVM-mediated ammonium supply could fuel bacterial anaerobic ammonium oxidation - a major loss process for fixed nitrogen in the ocean considerably. These estimates were based on the implicit assumption that hypoxia or anoxia in combination with hypercapnia (elevated pCO2) does not result in a down-regulation of ammonium excretion. We exposed calanoid copepods from the Eastern Tropical North Atlantic (ETNA; Undinula vulgaris and Pleuromamma abdominalis) and euphausiids from the Eastern Tropical South Pacific (ETSP; Euphausia mucronata) and the ETNA (Euphausia gibboides) to different temperatures, carbon dioxide and oxygen levels to study their survival, respiration and excretion rates at these conditions. An increase in temperature by 10 °C led to an approximately 2-fold increase of the respiration and excretion rates of U. vulgaris (Q10, respiration = 1.4; Q10, NH4-excretion = 1.6), P. abdominalis (Q10, respiration = 2.0; Q10, NH4-excretion = 2.4) and

  19. KINETICS OF DELIGNIFICATION AND CARBOHYDRATE DEGRADATION DURING OXYGEN BLEACHING

    Institute of Scientific and Technical Information of China (English)

    K.LNguyen

    2004-01-01

    Carbohydrate degradation during oxygen bleaching isassociated with cleavage reactions. It is apparent thatthe loss of the cellulose DPis strongly affected by(degree ofpolymisation) the extent of thedelignification. A strong linear correlation can beestablished between the DP of cellulose chains andthe residual lignin in the pulp. The Nuclear Growthconcept and Percolation Theory for heterogenoussystem can be combined to formulate kinetic modelsfor both the delignification and the degradation ofcarbohydrate. The models prediction is statisticallyrobust and can be applied to different pulps atdifferent bleachin~ conditions.

  20. Catalyst containing oxygen transport membrane

    Energy Technology Data Exchange (ETDEWEB)

    Lane, Jonathan A.; Wilson, Jamie R.; Christie, Gervase Maxwell; Petigny, Nathalie; Sarantopoulos, Christos

    2017-02-07

    A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a microstructure exhibiting substantially uniform pore size distribution as a result of using PMMA pore forming materials or a bi-modal particle size distribution of the porous support layer materials. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.

  1. Catalyst containing oxygen transport membrane

    Science.gov (United States)

    Christie, Gervase Maxwell; Wilson, Jamie Robyn; van Hassel, Bart Antonie

    2012-12-04

    A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a high average pore diameter and the intermediate porous layer has a lower permeability and lower pore diameter than the porous support layer. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.

  2. Synthesis and characterization of gallium-based perovskite- type dense membrane with oxygen semipermeability

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    La0.15Sr0.85Ga0.3Fe0.7O3-d (LSGFO) and La0.15Sr0.85Co0.3Fe0.7O3-d (LSCFO) mixed oxygen-ion and electron conducting oxides were synthesized by using a combined EDTA and citrate complexing method, and the corresponding dense membranes were fabricated. The properties of the oxide powders and membranes were characterized with combined SEM, XRD, H2-TPR, O2-TPD techniques, mechanical strength and oxygen permeation measurement. The results showed that LSGFO had much higher thermochemical stability than LSCFO due to the higher valence stability of Ga3+. After the temperature-programmed reduction by 5% H2 in Ar from 20℃ to 1020℃, the basic perovskite structure of LSGFO was successfully preserved. LSGFO also favors the oxygen vacancy formation better than LSCFO. Oxygen permeation measurement demonstrated that LSGFO had higher oxygen permeation flux than LSCFO, but they had similar activation energy for oxygen transportation, with a value of 110 and 117 kJ omol-1, respectively. The difference in oxygen permeation fluxes was correlated with the difference in oxygen vacancy concentrations for the two materials.

  3. Oxygen clamps in gold nanowires

    OpenAIRE

    Novaes, Frederico D.; da Silva, Antonio J. R.; da Silva, E. Z.; Fazzio, A.

    2005-01-01

    We investigate how the insertion of an oxygen atom in an atomically thin gold nanowire can affect its rupture. We find, using ab initio total energy density functional theory calculations, that O atoms when inserted in gold nanowires form not only stable but also very strong bonds, in such a way that they can extract atoms from a stable tip, serving in this way as a clamp that could be used to pull a string of gold atoms.

  4. Double Photoionization of Atomic Oxygen

    Science.gov (United States)

    Wickramarathna, Madhushani; Gorczyca, Thomas; Ballance, Connor; Stolte, Wayne

    2016-05-01

    Double photoionization of atomic oxygen was first measured at Aladdin, a second-generation synchrotron source, at lower resolution (Angel and Samson, PRA, 38, 5573, 1988). Here we present new experimental and theoretical results for the direct double photoionization of atomic oxygen. The experiment was performed at the Advanced Light Source for photon energies near the double-ionization threshold, revealing rich resonance structures converging to multiple single-ionization thresholds. State-of-the-art calculations were performed using the R-matrix with pseudostates (RMPS) method (P. G. Burke, R-matrix Theory of Atomic Collisions, Springer 2011) as implemented by Gorczya and Badnell (JPB, 30, 3897, 1997), and recently applied, in a converged representation, to the double photoionization of helium (T. W. Gorczyca et al., JPB, 46, 195201, 2013). The much-larger calculation required for oxygen, due to the many target state symmetries compared to helium, necessitated a parallel RMPS approach. Comparison between theoretical and experimental results shows overall qualitative agreement but also some puzzling discrepancies: experimental features that are not reproduced by the RMPS calculations.

  5. Magnetocaloric Pumping of Liquid Oxygen

    Science.gov (United States)

    Immer, Christopher; Kandula, Max; Lane, John; Youngquist, Robert

    2004-01-01

    The field-induced force density on a magnetic fluid is proportional to the magnetic susceptibility times the gradient of the magnetic field squared. The direction of the force is towards increasing magnetic field (positive gradient). Applying a magnetic field to a magnetic fluid will result in a force from all directions towards the location of peak field. Since the magnetic field is conservative and there are no magnetic monopoles, the net field-induced force on any fluid of constant susceptibly will be zero. The only manner to obtain a nonzero net field-induced force is to vary the susceptibility of the fluid. At the gas/liquid interface of liquid oxygen, the susceptibility varies drastically, and the exploitation of the resultant large net forces. An alternative method of varying the magnetic susceptibility is to vary the temperature of the fluid. The magnetic susceptibility of paramagnetic liquid oxygen obeys the Curie-Weiss law: it is inversely proportional to temperature. By applying a temperature gradient in the presence of a symmetric magnetic field, a nonzero net force results. Much of the theory of the so-called Magnetocaloric Effect has previously been developed for and applied to ferromagnetic fluids, or ferrofluids, but is readily applied to paramagnetic liquid oxygen.

  6. High-Pressure Oxygen Concentrator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA desires to generate and store gases including oxygen and nitrogen at sub-critical conditions as a part of its lunar and spacecraft atmospheric systems. Oxygen...

  7. Oxygen deficiency in the North Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A

    in contact with oxygen-depleted waters. Impacts of the oxygen deficiency on regional biogeochemistry, especially anaerobic nitrogen transformaions, are described. A comparison of the perrenial, mesopelagic OMZ in the open Northwestern Indian Ocean is made...

  8. Medical Oxygen Concentrator for Microgravity Operation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We have all seen people carrying portable oxygen tanks or concentrators to provide critical life support respiratory oxygen. Heavy, bulky, and for O2 concentrators,...

  9. Adjunctive Hyperbaric Oxygen Therapy or Alone Antibiotherapy? Methicillin Resistant Staphylococcus aureus Mediastinitis in a Rat Model

    Directory of Open Access Journals (Sweden)

    Tolga Kurt

    2015-10-01

    Full Text Available ABSTRACT OBJECTIVE: In the post-sternotomy mediastinitis patients, Staphylococcus aureus is the pathogenic microorganism encountered most often. In our study, we aimed to determine the efficacy of antibiotic treatment with vancomycin and tigecycline, alone or in combination with hyperbaric oxygen treatment, on bacterial elimination in experimental S. aureus mediastinitis. METHODS: Forty-nine adult female Wistar rats were used. They were randomly divided into seven groups, as follows: non-contaminated, contaminated control, vancomycin, tigecycline, hyperbaric oxygen, hyperbaric oxygen + vancomycin and hyperbaric oxygen + tigecycline. The vancomycin rat group received 10 mg/kg/day of vancomycin twice a day through intramuscular injection. The tigecycline group rats received 7 mg/kg/day of tigecycline twice a day through intraperitoneal injection. The hyperbaric oxygen group underwent 90 min sessions of 100% oxygen at 2.5 atm pressure. Treatment continued for 7 days. Twelve hours after the end of treatment, tissue samples were obtained from the upper part of the sternum for bacterial count assessment. RESULTS: When the quantitative bacterial counts of the untreated contaminated group were compared with those of the treated groups, a significant decrease was observed. However, comparing the antibiotic groups with the same antibiotic combined with hyperbaric oxygen, there was a significant reduction in microorganisms identified (P<0.05. Comparing hyperbaric oxygen used alone with the vancomycin and tigecycline groups, it was seen that the effect was not significant (P<0.05. CONCLUSION: We believe that the combination of hyperbaric oxygen with antibiotics had a significant effect on mediastinitis resulting from methicillin-resistant Staphylococcus aureus. Methicillin-resistant Staphylococcus aureus mediastinitis can be treated without requiring a multidrug combination, thereby reducing the medication dose and concomitantly decreasing the side effects.

  10. Kinetic bottlenecks to chemical exchange rates for deep-sea animals – Part 1: Oxygen

    Directory of Open Access Journals (Sweden)

    E. T. Peltzer

    2012-10-01

    Full Text Available Ocean warming will reduce dissolved oxygen concentrations which can pose challenges to marine life. Oxygen limits are traditionally reported simply as a static concentration thresholds with no temperature, pressure or flow rate dependency. Here we treat the oceanic oxygen supply potential for heterotrophic consumption as a dynamic molecular exchange problem analogous to familiar gas exchange processes at the sea surface. A combination of the purely physico-chemical oceanic properties temperature, hydrostatic pressure, and oxygen concentration defines the ability of the ocean to supply oxygen to any given animal. This general oceanic oxygen supply potential is modulated by animal specific properties such as the diffusive boundary layer thickness to define and limit maximal oxygen supply rates. Here we combine all these properties into formal, mechanistic equations defining novel oceanic properties that subsume various relevant classical oceanographic parameters to better visualize, map, comprehend, and predict the impact of ocean deoxygenation on aerobic life. By explicitly including temperature and hydrostatic pressure into our quantities, various ocean regions ranging from the cold deep-sea to warm, coastal seas can be compared. We define purely physico-chemical quantities to describe the oceanic oxygen supply potential, but also quantities that contain organism-specific properties which in a most generalized way describe general concepts and dependencies. We apply these novel quantities to example oceanic profiles around the world and find that temperature and pressure dependencies of diffusion and partial pressure create zones of greatest physical constriction on oxygen supply typically at around 1000 m depth, which coincides with oxygen concentration minimum zones. In these zones, which comprise the bulk of the world ocean, ocean warming and deoxygenation have a clear negative effect for aerobic life. In some shallow and warm waters the

  11. A Novel Electrochemical Oxygen Sensor for Determination of Ultra-low Oxygen Contents in Molten Metal

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A novel electrochemical oxygen sensor has been developed by using La-Al2O3 as solid electrolyte and Cr+Cr2O3 as reference electrode. The sensor not only can be used as normal oxygen sensor but also as an ultra-low oxygen sensor. Especially, it is very sensitive to measure ultra-low oxygen in molten metal. For estimating the accuracy of La-Al2O3 oxygen sensor, two series of oxygen activities in molten iron at different oxygen contents and different temperature were measured by both La-Al2O3 oxygen sensor and ZrO2 oxygen sensor. The theoretical values of oxygen activities in molten iron (3.30%C, in mass fraction) at 1723K and 1745K were also evaluated for comparing the measuring results of two sensors. At last, the error of measurement for La-Al2O3 oxygen sensor was discussed too.

  12. 高压氧结合脑活素治疗新生儿缺氧缺血性脑病148例疗效分析%Hyperbaric Oxygen Combined with Cerebrolysin in Treatment of 148 Cases of Neonatal Hypoxic- Ischemic Encephalopathy

    Institute of Scientific and Technical Information of China (English)

    李虎; 万俊; 凌厉; 刘桂华; 刘静

    2011-01-01

    The effect of hyperbaric oxygen for the treatment of neonatal hypoxic-ischemic encephalopathy was abserved. 296 cases of children with neonatal hypoxic-ischemic encephalopathy diagnosis and sub-standard in light, medium and severe were chosen for the study in our hospital neonatal wards from October 1999 to October 2006. They were divided into two groups randomly: control group (148 cases for the cerebrolysin group) and observation group (148 cases for the hyperbaric oxygen and cerebrolysin group). The YLCO. 5 - 1 infant hyperbaric oxygen chamber was setected, with the entire cabin of oxygen, and pressure 0. 05~0. 06 Mpa. Boost and buck 0. 5 hour, and the regulator one hour, during which a regulator in the 20 minute ventilation, one time per day, 7 times for a course of treatment. The earliest of the observation group getting-into the cabin for the first time was 25 hours after birth, while the average time for the first time getting-into the cabin was 60. 8 hours after birth. The effect of the observation group was better. According to the statistical analysis (x2 = 3. 95, P < 0. 05) , significant difference was showed, and the follow-up screening DDST NBNAp score and the observation group were significantly better than the control group. Early application of hyperbaric oxygen in the treatment of neonatal hypoxicischemic encephalopathy is effective, safe and reliable.%探讨高压氧治疗新生儿缺氧缺血性脑病的疗效.选择1999年10月至2006年10月我院新生儿病房中符合新生儿缺氧缺血性脑病诊断及分度标准的轻、中、重度患儿296例为研究对象.随机分成两组,对照组148例为脑活素治疗组,观察组148例为高压氧加脑活素治疗组,选用YLC0.5-1型婴儿高压氧舱,全舱给氧,压力0.05~0.06 Mpa.升压及降压各0.5 h,稳压1 h,其间稳压换气1次20 min,每天1次,7次为1疗程.本组首次入舱时间最早为生后25 h,平均首次人舱时间为60.8 h.观察组疗效明显高于

  13. 14 CFR 91.211 - Supplemental oxygen.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Supplemental oxygen. 91.211 Section 91.211... Requirements § 91.211 Supplemental oxygen. (a) General. No person may operate a civil aircraft of U.S. registry... the required minimum flight crew is provided with and uses supplemental oxygen for that part of...

  14. 46 CFR 147.85 - Oxygen.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Oxygen. 147.85 Section 147.85 Shipping COAST GUARD... Special Requirements for Particular Materials § 147.85 Oxygen. (a) Eighty five cubic meters (3000 standard cubic feet) or less of oxygen may be on board any vessel. (b) More than 85 m3 (3000 standard cubic...

  15. 41 CFR 50-204.67 - Oxygen.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Oxygen. 50-204.67 Section..., Vapors, Fumes, Dusts, and Mists § 50-204.67 Oxygen. The in-plant transfer, handling, storage, and utilization of oxygen as a liquid or a compressed gas shall be in accordance with Compressed Gas...

  16. Oxygen-carbon nanotubes as a chemotherapy sensitizer for paclitaxel in breast cancer treatment.

    Directory of Open Access Journals (Sweden)

    Yongkun Wang

    Full Text Available To study the in vivo and in vitro effects of adding oxygen carbon nanotubes (CNTs to chemotherapy for breast cancer.MCF-7 and SK-BR-3 breast cancer cells were co-cultured with paclitaxel and then exposed to oxygen-CNTs under hypoxic conditions. Cell proliferation, viability, and apoptosis rate were analyzed. Hypoxia-inducible factor-1 alpha (HIF-1α expression was measured using reverse transcription-polymerase chain reaction (RT-PCR and western blot. Nude mice were used as a human breast cancer model to explore the impact of oxygen-CNTs on the in vivo chemotherapeutic effect of paclitaxel.Oxygen-CNTs had no significant effects on the growth of breast cancer cells under normoxia and hypoxia. However, in the hypoxic environment, oxygen-CNTs significantly enhanced the inhibitory effect of paclitaxel on cell proliferation, as well as the apoptosis rate. Under hypoxia, downregulation of HIF-1α and upregulation of caspase-3, caspase-8, caspase-9, LC3 and Beclin-1 were observed when paclitaxel was combined with oxygen-CNT. Furthermore, addition of oxygen-CNTs to chemotherapy was found to significantly reduce tumor weight in the tumor-bearing mice model.Oxygen-CNTs can significantly increase the chemotherapeutic effect of paclitaxel on breast cancer cells. Oxygen-CNTs may be a potential chemosensitizer in breast cancer therapy.

  17. Effects of prone position ventilation combined with recruitment maneuver on oxygenation and intrapulmonary shunt in canines with acute respiratory distress syndrome%俯卧位通气联合肺复张手法对急性呼吸窘迫综合征犬氧合及肺内分流的影响

    Institute of Scientific and Technical Information of China (English)

    许启霞; 詹庆元; 王辰; 庞宝森; 李一鸣

    2008-01-01

    2.75、2.99,P均<0.05).结论 在小潮气量+呼气末正压的肺保护性通气基础上,俯卧位通气联合肺复张手法可以更有效地改善氧合,减少分流.%Objective To evaluate the effects of prone position ventilation(PPV)combined with recruitment maneuver(RM) on oxygenation and intrapulmonary shunting in oleic acid-induced acute respiratory distress syndrome(ARDS)in canines while ventilated with lung protective ventilation strategy.Methods ARDS was induced by oleic acid in 24 dogs,and the animals were ventilated with volume controlled ventilation(VCV),16 em H2O(1 cm H2O:0.098 kPa)of positive end-expiratory pressure(PEEP)and small tidal volumes(VT 10 ml/kg).All the dogs were randomly divided by random digit table into 4 groups(6 each),a control group(supine position,SP group),a prone position group(PP group),a supine position+RM group(SPRM group),and a prone position+RM group(PPRM group),and then were ventilated by VCV for 4 h.Arterial and mixed venous blood gas analyses were measured.Data were analyzed using the SPSS for windows(version 11.5).Results were expressed as (-x) ±s.Homogeneity of variance test was performed.The differences in means were calculated using one-way ANOVA.Post-hoc multiple comparisons of means were performed using Least Significant Difference.Nonparametric tests for several independent samples were performed to compare differences between the ranks in the groups studied.P value of<0.05 was considered statistically significant.Results (1) At 15 min,PaO2/FiO2 in the SPRM group,the PP group and the PPRM group[(368±45)mm Hg(1 mm Hg=0.133 kPa),(349±80)mm Hg,(423±43)mm Hg,respectively] was significantly higher than that in the SP group[(269±72)mm Hg,q=2.77,2.23,4.31,respectively,all P<0.05].At 2 h,PaO2/FiO2 in the PP group and the PPRM group[(401±82)mm Hg,(416±23)mm Hg,respectively] was significantly higher than that in the SP group[(232±40)mm Hg,q=3.99,4.35,respectively,all P<0.05].At 4 h,PaO2/FiO2 in the PPRM group[(384

  18. Simultaneous Monitoring of Vascular Oxygenation and Tissue Oxygen Tension of Breast Tumors Under Hyperbaric Oxygen Exposure

    Science.gov (United States)

    2008-04-01

    biological tissue, and allow for detection of specific light-absorbing chromophores in human in vivo, such as oxygenated and deoxygenated hemoglobin...spectra from tumor tissue. Briefly, continuous wave (CW) light from a 20 W tungsten-halogen light source (HL-2000HP, ocean optics, FL) is coupled...spectrometer (USB2000, Ocean optics, FL). The broadband light diffuse spectrometer provides reflectance spectra from 400 to 900 nm. According to

  19. Iridium-Doped Ruthenium Oxide Catalyst for Oxygen Evolution

    Science.gov (United States)

    Valdez, Thomas I.; Narayan, Sri R.; Billings, Keith J.

    2011-01-01

    NASA requires a durable and efficient catalyst for the electrolysis of water in a polymer-electrolyte-membrane (PEM) cell. Ruthenium oxide in a slightly reduced form is known to be a very efficient catalyst for the anodic oxidation of water to oxygen, but it degrades rapidly, reducing efficiency. To combat this tendency of ruthenium oxide to change oxidation states, it is combined with iridium, which has a tendency to stabilize ruthenium oxide at oxygen evolution potentials. The novel oxygen evolution catalyst was fabricated under flowing argon in order to allow the iridium to preferentially react with oxygen from the ruthenium oxide, and not oxygen from the environment. Nanoparticulate iridium black and anhydrous ruthenium oxide are weighed out and mixed to 5 18 atomic percent. They are then heat treated at 300 C under flowing argon (in order to create an inert environment) for a minimum of 14 hours. This temperature was chosen because it is approximately the creep temperature of ruthenium oxide, and is below the sintering temperature of both materials. In general, the temperature should always be below the sintering temperature of both materials. The iridium- doped ruthenium oxide catalyst is then fabricated into a PEM-based membrane- electrode assembly (MEA), and then mounted into test cells. The result is an electrolyzer system that can sustain electrolysis at twice the current density, and at the same efficiency as commercial catalysts in the range of 100-200 mA/sq cm. At 200 mA/sq cm, this new system operates at an efficiency of 85 percent, which is 2 percent greater than commercially available catalysts. Testing has shown that this material is as stable as commercially available oxygen evolution catalysts. This means that this new catalyst can be used to regenerate fuel cell systems in space, and as a hydrogen generator on Earth.

  20. Earliest land plants created modern levels of atmospheric oxygen

    Science.gov (United States)

    Lenton, Timothy M.; Dahl, Tais W.; Daines, Stuart J.; Mills, Benjamin J. W.; Ozaki, Kazumi; Saltzman, Matthew R.; Porada, Philipp

    2016-08-01

    The progressive oxygenation of the Earth’s atmosphere was pivotal to the evolution of life, but the puzzle of when and how atmospheric oxygen (O2) first approached modern levels (˜21%) remains unresolved. Redox proxy data indicate the deep oceans were oxygenated during 435-392 Ma, and the appearance of fossil charcoal indicates O2 >15-17% by 420-400 Ma. However, existing models have failed to predict oxygenation at this time. Here we show that the earliest plants, which colonized the land surface from ˜470 Ma onward, were responsible for this mid-Paleozoic oxygenation event, through greatly increasing global organic carbon burial—the net long-term source of O2. We use a trait-based ecophysiological model to predict that cryptogamic vegetation cover could have achieved ˜30% of today’s global terrestrial net primary productivity by ˜445 Ma. Data from modern bryophytes suggests this plentiful early plant material had a much higher molar C:P ratio (˜2,000) than marine biomass (˜100), such that a given weathering flux of phosphorus could support more organic carbon burial. Furthermore, recent experiments suggest that early plants selectively increased the flux of phosphorus (relative to alkalinity) weathered from rocks. Combining these effects in a model of long-term biogeochemical cycling, we reproduce a sustained +2‰ increase in the carbonate carbon isotope (δ13C) record by ˜445 Ma, and predict a corresponding rise in O2 to present levels by 420-400 Ma, consistent with geochemical data. This oxygen rise represents a permanent shift in regulatory regime to one where fire-mediated negative feedbacks stabilize high O2 levels.

  1. Ammonium excretion and oxygen respiration of tropical copepods and euphausiids exposed to oxygen minimum zone conditions

    Directory of Open Access Journals (Sweden)

    R. Kiko

    2015-10-01

    Full Text Available Calanoid copepods and euphausiids are key components of marine zooplankton communities worldwide. Most euphausiids and several copepod species perform diel vertical migrations (DVMs that contribute to the export of particulate and dissolved matter to midwater depths. In vast areas of the global ocean, and in particular in the eastern tropical Atlantic and Pacific, the daytime distribution depth of many migrating organisms corresponds to the core of the oxygen minimum zone (OMZ. At depth, the animals experience reduced temperature and oxygen partial pressure (pO2 and an increased carbon dioxide partial pressure (pCO2 compared to their near-surface nighttime habitat. Although it is well known that low oxygen levels can inhibit respiratory activity, the respiration response of tropical copepods and euphausiids to relevant pCO2, pO2 and temperature conditions remains poorly parameterized. Further, the regulation of ammonium excretion at OMZ conditions is generally not well understood. It was recently estimated that DVM-mediated ammonium supply considerably fuels bacterial anaerobic ammonium oxidation – a major loss process for fixed nitrogen in the ocean. These estimates were based on the implicit assumption that hypoxia or anoxia in combination with hypercapnia (elevated pCO2 does not result in a downregulation of ammonium excretion. Here we show that exposure to OMZ conditions can result in strong depression of respiration and ammonium excretion in calanoid copepods and euphausiids from the Eastern Tropical North Atlantic and the Eastern Tropical South Pacific. These physiological responses need to be taken into account when estimating DVM-mediated fluxes of carbon and nitrogen into OMZs.

  2. Influence of oxygen on wound healing.

    Science.gov (United States)

    Yip, Wai Lam

    2015-12-01

    Oxygen has an important role in normal wound healing. This article reviews the evidence concerning the role of oxygen in wound healing and its influence on the different stages of wound healing. The evidence reviewed has demonstrated that improving oxygenation may be helpful in limiting wound infection, although there is a lack of good quality studies on the role of oxygen in the proliferative phase and in reepithelialisation. Overall, the relationship between oxygen and wound healing is complex. Knowledge of this aspect is important as many treatment modalities for refractory wounds are based on these principles.

  3. 局部氧疗法对高温复合创伤大鼠创面肌肉组织影响的光镜观察研究%The optical microscopic observation on the effects of rats of hyperthermia combined with trauma through topical oxygen therapy

    Institute of Scientific and Technical Information of China (English)

    杨瑞; 刘喜文; 杨群; 徐巧玲

    2008-01-01

    Objective Through the optical microscopic observation to investigate the pathological influence of topical oxygen therapy on wounds of rats' muscles in hot and humid environment. Method The rat traumatic models were established. Twenty-four rats were randomly divided into four groups, including normal envi-ronment comparison group (NEC group, n=6), normal environment oxygen therapy group (NEO group, n=6). hot and humid environment comparison group (HHE group, n=6), hot and humid environment oxygen therapy group (HHO group, n=6).Then all rats were sampled to observe the changes of rats' muscle under optical microscope. Results Pathologic histology of muscle cells were obviously changed in HHE group. In these rats. disorganized myofibrillae with some loss of myofilaments. The damage of the muscle fibers in HHO group were better than that in HHE group. The damage of muscle ceils in NEC group were slighter than that in HHE group, the muscle of rats in NEO group are all normal. Conclusion In hot and humid en-vironment pathologic histology changes of wounds were serious, topical oxygen therapy could relieve muscle tissue ultrastructures change.%目的 通过光镜观察探讨局部氧疗法对高温复合创伤大鼠创面肌肉组织的影响,为湿热环境的创伤伤口护理提供实验依据.方法 建立24只大鼠腹部创伤模型,随机将其分为常温对照组、常温氧疗组、高温对照组和高温氧疗组4组,6只/组,让其分别接受常温暴露、常温氧疗、高温露和高温氧疗,然后进行光镜观察.结果 高温对照组创面肌肉的组织形态变化最为剧烈,肌纤维明显变性萎缩甚至变性坏死成碎片,毛细血管扩张充血明显,大量炎性细胞入侵组织,组织间隙水肿严重;高温氧疗组明显好于高温对照组,肌纤维仅肿胀而未发生萎缩变性.结论 高温复合创伤应激比单因素的创伤应激显著,高温高湿环境创伤组织肌纤维损伤严重,局部氧疗法可降低高温

  4. 亚低温联合高压氧治疗新生儿缺血缺氧性脑病的临床研究%Clinical research of mild hypothermia combined with hyperbaric oxygen in the treatment of neonatal hypoxic-ischemic encephalopathy

    Institute of Scientific and Technical Information of China (English)

    王长芹

    2010-01-01

    目的 探讨亚低温联合高压氧治疗新生儿缺血缺氧性脑病(HIE)的临床效果.方法 将75例新生儿HIE患者随机分为高压氧联合亚低温治疗组(治疗组)40例和对照组35 例;对照组接受常规综合治疗,治疗组在此基础上行早期高压氧联合亚低温治疗.两组患儿在生后4、14 d进行新生儿神经行为测定,3、6、12个月进行婴幼儿智能运动发育检查测定.结果 两组患儿出生后4 d测定值比较差异无统计学意义(t=0126,P>0.05),生后14 d测定值高压氧组与对照组比较差异有统计学意义(t=2.48,P0.05).The NBNA score when the newborns were 14 days had obvious difference between the two groups(t=2.48,P<0.05).The index of mental and psychomotor development when the newborns were 3 months,6months and 12 months in mild hypothermia complicated with heperbaric oxygen therapy group was obviously higher than that in control group.There were obvious difference between the two groups(P<0.05).Conclusions Mild hypothermia complicated with heperbaric oxygen therapy have obvious near ang long neurological protective action on neonatal hypoxic-ischemic encephalopathy and can improve the living quality.The treatment effect is positive.

  5. Investigation of novel zirconium based perovskite-type mixed conducting membranes for oxygen separation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A series of BaZr0.2Co0.8-xFexO3-δ materials for oxygen separation were synthesized through a citric and EDTA acid combined complexing method,and their crystal structures,oxygen permeabilities,sintering and sealing abilities were investigated. The results showed that the cubic perovskite structure was formed for materials in the composition range investigated. Oxygen permeation flux and stability,as well as sintering and sealing abilities of the synthesized materials were increased or improved apparently due to the introduction of zirconium. For example,the oxygen permeation flux reached 0.8 mL/min·cm2 when x = 0.2 or 0.3 at 950℃,and a stable time-related oxygen permeation flux was found for the BaZr0.2Co0.3Fe0.5O3-δ membrane at 800℃.

  6. [Use of hyperbaric oxygenation for wound management].

    Science.gov (United States)

    Berner, Juan Enrique; Vidal, Pedro; Will, Patrick; Castillo, Pablo

    2014-12-01

    Hyperbaric oxygenation consists in exposing patients to increased gas pressures while inhaling pure oxygen. It involves the use of hyperbaric chambers that can double or triple gas pressure inside them. Hyperbaric oxygenation may be useful in different clinical situations, but mostly for the treatment of decompression syndrome. In the last decades, it has been used for the management of different kinds of wounds. Hyperbaric oxygenation not only increases the delivery of oxygen to damaged tissues, but also stimulates angiogenesis, collagen synthesis, stem cell migration and local immune response. Clinical trials that have addressed the use of hyperbaric oxygenation are difficult to compare due to their heterogeneity in terms of experimental design, kind of injuries involved and assessment of outcome. Even though, most studies support the concept that hyperbaric oxygenation accelerates the healing process.

  7. Effect of longitudinal oxygen gradients on effectiveness of manipulation of tumor oxygenation.

    Science.gov (United States)

    Erickson, Kristian; Braun, Rod D; Yu, Daohai; Lanzen, Jennifer; Wilson, David; Brizel, David M; Secomb, Timothy W; Biaglow, John E; Dewhirst, Mark W

    2003-08-01

    The purpose of this study was to test the hypothesis that longitudinal O(2) gradients in tumor affect response to manipulation of oxygenation. Previously we showed that pO(2) is higher on the fascial than the tumor surface of the R3230Ac rat mammary carcinoma when growing in a dorsal skin-fold window chamber, reflecting a longitudinal oxygen gradient. Magnetic resonance angiography verified prior results: the fascial surface has arterioles and higher vascular density than tumor; and the tumor surface has no arterioles. Phosphorescence lifetime imaging was used to measure each surface hypoxic percentage (HP; percentage of pixels fascial surface had a smaller HP (median = 2.72%) than tumor (median = 27.94%; P = 0.0002) at baseline. HP on the fascial surface was positively correlated with HP on the tumor surface (P = 0.0067). HP decreased on the fascial surface after either sugar + O(2) (mannitol P = 0.03; glucose P = 0.06; combined P = 0.002), but HP did not change on the tumor surface. Therefore, the tumor surface is refractory to improvement in pO(2) with this method. Additional refinements may be needed to improve pO(2) of analogous regions in larger tumors; mechanism-driven suggestions are provided.

  8. Photoacoustic lifetime imaging of dissolved oxygen using methylene blue

    Science.gov (United States)

    Ashkenazi, Shai

    2010-07-01

    Measuring distribution of dissolved oxygen in biological tissue is of prime interest for cancer diagnosis, prognosis, and therapy optimization. Tumor hypoxia indicates poor prognosis and resistance to radiotherapy. Despite its major clinical significance, no current imaging modality provides direct imaging of tissue oxygen. We present preliminary results demonstrating the potential of photoacoustic lifetime imaging (PALI) for noninvasive, 3-D imaging of tissue oxygen. The technique is based on photoacoustic probing of the excited state lifetime of methylene blue (MB) dye. MB is an FDA-approved water soluble dye with a peak absorption at 660 nm. A double pulse laser system (pump probe) is used to excite the dye and probe its transient absorption by detecting photoacoustic emission. The relaxation rate of MB depends linearly on oxygen concentration. Our measurements show high photoacoustic signal contrast at a probe wavelength of 810 nm, where the excited state absorption is more than four times higher than the ground state absorption. Imaging of a simple phantom is demonstrated. We conclude by discussing possible implementations of the technique in clinical settings and combining it with photodynamic therapy (PDT) for real-time therapy monitoring.

  9. Direct Oxygen Abundances for Low Luminosity LVL Galaxies

    CERN Document Server

    Berg, Danielle A; Marble, Andrew R; van Zee, Liese; Engelbracht, Charles W; Lee, Janice C; Kennicutt, Robert C; Jr.,; Calzetti, Daniela; Dale, Daniel A; Johnson, Benjamin D

    2012-01-01

    We present MMT spectroscopic observations of HII regions in 42 low luminosity galaxies in the LVL. For 31 galaxies, we measured the temperature sensitive [O III] line at a strength of 4 sigma or greater, and thus determine direct oxygen abundances. Our results provide the first direct estimates of oxygen abundance for 19 galaxies. Oxygen abundances were compared to B-band and 4.5 micron luminosities and stellar masses in order to characterize the luminosity-metallicity (L-Z) and mass-metallicity (M-Z) relationships at low-luminosity. We present and analyze a "Combined Select" sample composed of 38 objects (drawn from our parent sample and the literature) with direct oxygen abundances and reliable distance determinations (TRGB or Ceph). Consistent with previous studies, the B-band and 4.5 micron L-Z relationships were found to be 12+log(O/H)=(6.27+/-0.21)+(-0.11+/-0.01)M_B and 12+log(O/H)=(6.10+/-0.21)+(-0.10+/-0.01)M_[4.5] (sigma=0.15 and 0.14). For this sample, we derive a M-Z relationship of 12+log(O/H)=(5....

  10. Mode transitions and electronegativity in oxygen CCP and ICP

    Science.gov (United States)

    Meichsner, Juergen; Wegner, Thomas

    2016-09-01

    Mode transitions in 13.56 MHz oxygen radio frequency plasmas (CCP, ICP) and their impact on the electron heating mechanisms and electronegativity were studied by advanced plasma diagnostics. In particular, Langmuir probe measurements, Gaussian beam microwave interferometry (160 GHz) coupled with laser photodetachment of negative oxygen ions, as well as the (phase resolved) optical emission and VUV absorption spectroscopy, and ion mass spectrometry are taken into consideration. With increasing RF power a transition between high and low electronegativity was found both in CCP and ICP discharge configuration. Thereby, the changed electron heating mechanisms, e.g., the alpha-gamma mode transition in CCP and the E-H mode transition in ICP is combined with the change of electronegativity. In strongly asymmetric CCP at moderate pressure the emission of secondary negative ions at the powered electrode have to be considered, too. Thereby, pseudo secondary electrons may be produced due to collision detachment of negative ion by metastables. During the E-H mode transition in oxygen ICP, the increasing gas temperature and the metastables influences significantly the oxygen kinetics. Supported by the DFG Collaborative Research Centre Transregio 24 ``Fundamentals of Complex Plasmas''.

  11. Calibrated BOLD using direct measurement of changes in venous oxygenation.

    Science.gov (United States)

    Driver, Ian D; Hall, Emma L; Wharton, Samuel J; Pritchard, Susan E; Francis, Susan T; Gowland, Penny A

    2012-11-15

    Calibration of the BOLD signal is potentially of great value in providing a closer measure of the underlying changes in brain function related to neuronal activity than the BOLD signal alone, but current approaches rely on an assumed relationship between cerebral blood volume (CBV) and cerebral blood flow (CBF). This is poorly characterised in humans and does not reflect the predominantly venous nature of BOLD contrast, whilst this relationship may vary across brain regions and depend on the structure of the local vascular bed. This work demonstrates a new approach to BOLD calibration which does not require an assumption about the relationship between cerebral blood volume and cerebral blood flow. This method involves repeating the same stimulus both at normoxia and hyperoxia, using hyperoxic BOLD contrast to estimate the relative changes in venous blood oxygenation and venous CBV. To do this the effect of hyperoxia on venous blood oxygenation has to be calculated, which requires an estimate of basal oxygen extraction fraction, and this can be estimated from the phase as an alternative to using a literature estimate. Additional measurement of the relative change in CBF, combined with the blood oxygenation change can be used to calculate the relative change in CMRO(2) due to the stimulus. CMRO(2) changes of 18 ± 8% in response to a motor task were measured without requiring the assumption of a CBV/CBF coupling relationship, and are in agreement with previous approaches.

  12. Steam reforming of light oxygenates

    DEFF Research Database (Denmark)

    Trane-Restrup, Rasmus; Resasco, Daniel E; Jensen, Anker Degn

    2013-01-01

    Steam reforming (SR) of ethanol, acetic acid, acetone, acetol, 1-propanol, and propanal has been investigated over Ni/MgAl2O4 at temperatures between 400 and 700 degrees C and at a steam-to-carbon-ratio (S/C) of 6. The yield of H-2 and conversion increased with temperature, while the yield of by-products...... decreased with temperature in the SR of the investigated compounds. The yield of H2 approached the thermodynamic limit at the highest temperatures investigated. No significant differences in conversion as a function of temperature among the different model compounds were observed. However, the product...... distribution depended on the model compound, and C-3-oxygenates produced a larger fraction of by-products compared to C-2-oxygenates. Temperatures of 600 degrees C or above were generally needed to minimize the fraction of by-products and obtain a syngas containing mainly CO, CO2, H-2, and H2O with only traces...

  13. Hyperbaric oxygen and wound healing

    Directory of Open Access Journals (Sweden)

    Sourabh Bhutani

    2012-01-01

    Full Text Available Hyperbaric oxygen therapy (HBOT is the use of 100% oxygen at pressures greater than atmospheric pressure. Today several approved applications and indications exist for HBOT. HBOT has been successfully used as adjunctive therapy for wound healing. Non-healing wounds such as diabetic and vascular insufficiency ulcers have been one major area of study for hyperbaric physicians where use of HBOT as an adjunct has been approved for use by way of various studies and trials. HBOT is also indicated for infected wounds like clostridial myonecrosis, necrotising soft tissue infections, Fournier′s gangrene, as also for traumatic wounds, crush injury, compartment syndrome, compromised skin grafts and flaps and thermal burns. Another major area of application of HBOT is radiation-induced wounds, specifically osteoradionecrosis of mandible, radiation cystitis and radiation proctitis. With the increase in availability of chambers across the country, and with increasing number of studies proving the benefits of adjunctive use for various kinds of wounds and other indications, HBOT should be considered in these situations as an essential part of the overall management strategy for the treating surgeon.

  14. Synthesis and characterization of gallium-based perovskitetype dense membrane with oxygen semipermeability

    Institute of Scientific and Technical Information of China (English)

    丛铀; 邵宗平; 杨维慎; 熊国兴; 林励吾

    2001-01-01

    La0.15Sr0.85Ga0.3Fe0.7O3-δ(LSGFO) and La0.15Sr0.85Co0.3Fe0.7O3-δ(LSCFO) mixed oxygen-ion and electron conducting oxides were synthesized by using a combined EDTA and citrate complexing method, and the corresponding dense membranes were fabricated. The properties of the oxide powders and membranes were characterized with combined SEM, XRD, H2-TPR, O2-TPD techniques, mechanical strength and oxygen permeation measurement. The results showed that LSGFO had much higher thermochemical stability than LSCFO due to the higher valence stability of Ga3+. After the temperature-programmed reduction by 5% H2 in Ar from 20℃to 1020℃, the basic perovskite structure of LSGFO was successfully preserved. LSGFO also favors the oxygen vacancy formation better than LSCFO. Oxygen permeation measurement demonstrated that LSGFO had higher oxygen permeation flux than LSCFO, but they had similar activation energy for oxygen transportation, with a value of 110 and 117 kJ ?mol-1, respectively. The difference in oxygen permeation f

  15. Hydroxylamine as an oxygen nucleophile: substitution of sulfonamide by a hydroxyl group in benzothiazole-2-sulfonamides.

    Science.gov (United States)

    Kamps, Jos J A G; Belle, Roman; Mecinović, Jasmin

    2013-02-21

    Benzothiazole-2-sulfonamides react with an excess of hydroxylamine in aqueous solutions to form 2-hydroxybenzothiazole, sulfur dioxide, and the corresponding amine. Mechanistic studies that employ a combination of structure-reactivity relationships, oxygen labeling experiments, and (in)direct detection of intermediates and products reveal that the reaction proceeds via oxygen attack, and that oxygen incorporated in the 2-hydroxybenzothiazole product derives from hydroxylamine. The reaction, which is performed under mild conditions, can be used as a deprotection method for cleavage of benzothiazole-2-sulfonyl-protected amino acids.

  16. Characterization of hemodynamics and oxygenation in the renal cortex of rats

    Science.gov (United States)

    Grosenick, Dirk; Wabnitz, Heidrun; Macdonald, Rainer; Niendorf, Thoralf; Cantow, Kathleen; Flemming, Bert; Arakelyan, Karen; Seeliger, Erdmann

    2015-03-01

    We have performed a pre-clinical study on 13 rats to investigate the potential of near-infrared spectroscopy for quantification of hemoglobin concentration and oxygen saturation of hemoglobin in the renal cortex of small animals. These measurements were combined with laser-Doppler fluxmetry and a fluorescence quenching technique for quantification of tissue oxygen tension. Hemoglobin concentration and oxygen saturation were determined from experimental data by a Monte Carlo model. The methods were applied to investigate and compare temporal changes during several types of interventions such as arterial and venous occlusions, as well as hyperoxia, hypoxia and hypercapnia induced by different mixtures of the inspired gas.

  17. Atmospheric oxygen regulation at low Proterozoic levels by incomplete oxidative weathering of sedimentary organic carbon

    Science.gov (United States)

    Daines, Stuart J.; Mills, Benjamin J. W.; Lenton, Timothy M.

    2017-02-01

    It is unclear why atmospheric oxygen remained trapped at low levels for more than 1.5 billion years following the Paleoproterozoic Great Oxidation Event. Here, we use models for erosion, weathering and biogeochemical cycling to show that this can be explained by the tectonic recycling of previously accumulated sedimentary organic carbon, combined with the oxygen sensitivity of oxidative weathering. Our results indicate a strong negative feedback regime when atmospheric oxygen concentration is of order pO2~0.1 PAL (present atmospheric level), but that stability is lost at pO2biological productivity and resultant organic carbon burial drove the Great Oxidation Event.

  18. Oxygen reduction on carbon supported platinum catalysts in high temperature polymer electrolytes

    DEFF Research Database (Denmark)

    Qingfeng, Li; Hjuler, Hans Aage; Bjerrum, Niels

    2000-01-01

    improve the oxygen reduction kinetics due to increased oxygen solubility and suppressed adsorption of phosphoric acid anions. Further enhancement of the catalytic activity can be obtained by operating the polymer electrolytes at higher temperatures. Efforts have been made to develop a polymer electrolyte......Oxygen reduction on carbon supported platinum catalysts has been investigated in H3PO4, H3PO4-doped Nafion and polybenzimidazole (PBI) polymer electrolytes in a temperature range up to 190 degrees C. Compared with pure H3PO4, the combination of H3PO4 and polymer electrolytes can significantly...

  19. Effect of intermittent light on oxygen production of Spirulina platensis; Supirurina no sansohassei ni oyobosu shukiko no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Ohira, Y.; Abe, T.; Kuga, Y.; Ando, K. [Muroran Institute of Technology, Hokkaido (Japan). Dept. of Applied Chemistry

    2000-05-10

    S. platensis media were irradiated with intermittent light interrupted by a slit in a rotating disk. The effects of the light periodicity, irradiation time, and dark time during a cycle on the oxygen production rate of S. platensis are experimentally discussed. The following oxygen production ratio was used as the index to compare the oxygen production rate between the intermittent light and the continuous light. (Oxygen production ratio)=(Oxygen volume produced by intermittent light)/(Opening ratio of the disk)(Oxygen volume produced by continuous light). When S. platensis media were irradiated with the intermittent light having a periodicity of 0.0044-0.60 s{sup -1}, the oxygen production ratio increased with an increased with an increase in light periodicity. The value of the oxygen production ratio is greater than one when the irradiation time during a cycle is shorter than 1 s. Under these conditions, the oxygen production ratio increases with increasing dark time. the effect of the intermittent light on the oxygen production rate of S. platensis was found to be qualitatively described by the simple model which combined the oxygen production rate of S. platensis and the respiration rate. (author)

  20. Workshop on Oxygen in the Terrestrial Planets

    Science.gov (United States)

    2004-01-01

    This volume contains abstracts that have been accepted for presentation at the Workshop on Oxygen in the Terrestrial Planets, July 20-23,2004, Santa Fe, New Mexico. The contents include: 1) Experimental Constraints on Oxygen and Other Light Element Partitioning During Planetary Core Formation; 2) In Situ Determination of Fe(3+)/SigmaFe of Spinels by Electron Microprobe: An Evaluation of the Flank Method; 3) The Effect of Oxygen Fugacity on Large-Strain Deformation and Recrystallization of Olivine; 4) Plagioclase-Liquid Trace Element Oxygen Barometry and Oxygen Behaviour in Closed and Open System Magmatic Processes; 5) Core Formation in the Earth: Constraints from Ni and Co; 6) Oxygen Isotopic Compositions of the Terrestrial Planets; 7) The Effect of Oxygen Fugacity on Electrical Conduction of Olivine and Implications for Earth s Mantle; 8) Redox Chemical Diffusion in Silicate Melts: The Impact of the Semiconductor Condition; 9) Ultra-High Temperature Effects in Earth s Magma Ocean: Pt and W Partitioning; 10) Terrestrial Oxygen and Hydrogen Isotope Variations: Primordial Values, Systematics, Subsolidus Effects, Planetary Comparisons, and the Role of Water; 11) Redox State of the Moon s Interior; 12) How did the Terrestrial Planets Acquire Their Water?; 13) Molecular Oxygen Mixing Ratio and Its Seasonal Variability in the Martian Atmosphere; 14) Exchange Between the Atmosphere and the Regolith of Mars: Discussion of Oxygen and Sulfur Isotope Evidence; 15) Oxygen and Hydrogen Isotope Systematics of Atmospheric Water Vapor and Meteoric Waters: Evidence from North Texas; 16) Implications of Isotopic and Redox Heterogeneities in Silicate Reservoirs on Mars; 17) Oxygen Isotopic Variation of the Terrestrial Planets; 18) Redox Exchanges in Hydrous Magma; 19) Hydrothermal Systems on Terrestrial Planets: Lessons from Earth; 20) Oxygen in Martian Meteorites: A Review of Results from Mineral Equilibria Oxybarometers; 21) Non-Linear Fractionation of Oxygen Isotopes Implanted in

  1. Research on Technology of Pressure Pretreatment with Oxygen for Refractory Gold Ores

    Institute of Scientific and Technical Information of China (English)

    Liu Shengming; Sun Tichang; Chen Jinghe; Wang Dianzuo

    2007-01-01

    An combined technology of pressure pretreatment with oxygen on refractory gold ores is pointed out and discussed on this paper, according to the experiments included the test in 1kg grade batch pressure pretreatment with oxygen of the concentrate from the refractory gold ores of Dongbeizhai in Sichuan province, which is called the most refractory gold ores in China. It is shown that gold recovery reach 91.73% in the combined process which is described as follows: The flotation of the sulphide gold ores is under controlled conditions, producing the concentrate for pressure pretreatment with oxygen in acidic medium and the middling for the pressure pretreatment with oxygen in alkaline medium. The thickening and washing process substitute the pressure filtration process of the pulp after pressure pretreatment. The thick slimes of the two kinds of pressure pretreatment were mixed and then enter the CIL process for simplifying the flowsheet. The possible superabundance of acid of pressure pretreatment with oxygen in acidic medium was neutralized by the tailings of flotation and the cost of neutralization will be lower. The combined technology of pressure pretreatment with oxygen has the same advantages as the normal technology of pressure pretreatment and both is helpful for environment protection.

  2. Noninvasive tumor oxygen imaging by photoacoustic lifetime imaging integrated with photodynamic therapy

    Science.gov (United States)

    Shao, Qi; Biel, Merrill A.; Ashkenazi, Shai

    2014-03-01

    Oxygen plays a major role in cancer biology and tumor progression. In PDT, the reduction in efficacy is directly related to lack of oxygen because its molecular mechanism relies on oxygen as an energy mediator. Measuring tumor oxygenation can provide physicians with better diagnosis and optimization of treatment plans. However, clinical tools for directly assessing tissue oxygenation are limited. The gold standard is oxygen needle electrode, which is invasive and measures oxygen level at a single location. We present our work on developing a combined treatment-imaging modality that integrates PDT and photoacoustic oxygen imaging. We propose a system designed for clinical treatments of cancer of the oral cavity. Tissue oxygen imaging is performed by applying Photoacoustic Lifetime Imaging (PALI). This technology relies on photoacoustic probing of oxygen-dependent excitation lifetime of Methylene Blue. The dye is excited by the same wavelength of illumination source for PDT. Once excited, the population of photosensitizer molecules at triplet state has a lifetime depending on the oxygen level. The transition from excited triplet state to ground state can be probe by another laser, which generate photoacoustic signal that is used to map the lifetime. The lifetime map is then converted to pO2 distribution. We expect that PDT efficacy can be improved by applying PALI imaging feedback in real-time to determine, and individually optimize, O2-enriched gas breathing parameters and PDT light-dose during treatment. Successful implementation of PALI in PDT can also drive its application in guiding other cancer treatments that are affected by hypoxia.

  3. Fuelling the palaeoatmospheric oxygen debate: how much atmospheric oxygen is required for ignition and propagation of smouldering fires?

    Science.gov (United States)

    Belcher, Claire M.; Hadden, Rory; McElwain, Jennifer C.; Rein, Guillermo

    2010-05-01

    Fire is a natural process integral to ecosystems at a wide range of temporal and spatial scales and is a key driver of change in the Earth system. Fire has been a major influence on Earth's systems since the Carboniferous. Whilst, climate is considered the ultimate control on global vegetation, fire is now known to play a key role in determining vegetation structure and composition, such that many of the world's ecosystems can be considered fire-dependant. Products of fire include chars, soots and aromatic hydrocarbon species all of which can be traced in ancient through to modern sediments. Atmospheric oxygen has played a key role in the development of life on Earth, with the rise of oxygen in the Precambrian being closely linked to biological evolution. Variations in the concentration of atmospheric oxygen throughout the Phanerozoic are predicted from models based on geochemical cycling of carbon and sulphur. Such models predict that low atmospheric oxygen concentrations prevailed in the Mesozoic (251-65ma) and have been hypothesised to be the primary driver of at least two of the ‘big five' mass extinction events in the Phanerozoic. Here we assess the levels of atmospheric oxygen required to ignite a fire and infer the likely levels of atmospheric oxygen to support smouldering combustion. Smouldering fire dynamics and its effects on ecosystems are very different from flaming fires. Smouldering fires propagate slowly, are usually low in temperature and represent a flameless form of combustion. These fires creep through organic layers of forest ground and peat lands and are responsible for a large fraction of the total biomass consumed in wildfires globally and are also a major contributor of carbon dioxide to the atmosphere. Once ignited, they can persist for long periods of time (months, years) spreading over very extensive areas of forest and deep into soil. Smouldering fires are therefore, the oldest continuously burning fires on Earth. We have combined

  4. The influence of ultraviolet blood irradiation and oxygenation on oxygen free radicals metabolism in rabbits with soman intoxication

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To investigate the effect of ultraviolet blood irradiation and oxygenation (UBIO) on the metabolism of oxygen free radicals in rabbits with acute soman intoxication. Methods: One hundred rabbits were randomly divided into 5 groups: normal control group, intoxication group, routine therapy group, UBIO therapy group and combined therapy group. After 14 d, the concentration of malondiadehyde (MDA) and activity of superoxide dismutase (SOD), glutathionperoxidase (GSH-Px), catalase (CAT)and total antioxidative capacity (T-AOC) in serum were determined respectively. Results: Compared with the normal control group, the concentration of MDA and activity of CAT in the intoxication group were significantly higher (P < 0. 05 ), but SOD, GSH-Px activity and T-AOC were significantly lower (P<0.05). After UBIO or combined therapy, serum MDA level was significantly lower in comparison with intoxication group (P<0.05), but the activity of SOD, GSH-Px, CAT and T AOC were higher than intoxication group(P<0.05). Conclusion: There is an obvious oxygen free radical injury in rabbits with acute soman intoxication. UBIO can improve the antioxidation ability of rabbits and may be applied to treat acute soman intoxication as adjunctive therapy.

  5. 14 CFR 25.1441 - Oxygen equipment and supply.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Oxygen equipment and supply. 25.1441... Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, the... oxygen available in each source of supply. (d) The oxygen flow rate and the oxygen equipment...

  6. Hyperbaric oxygen therapy for idiopathic sudden sensorineural hearing loss.

    Science.gov (United States)

    Murphy-Lavoie, H; Piper, S; Moon, R E; Legros, T

    2012-01-01

    Idiopathic sudden sensorineural hearing loss (ISSHL) is the newest indication approved by the Undersea and Hyperbaric Medical Society's Hyperbaric Oxygen Therapy Committee. Idiopathic sudden sensorineural hearing loss appears to be characterized by hypoxia in the perilymph and therefore the scala tympani and the organ of Corti. A review of the literature reveals more than 100 publications evaluating the use of hyperbaric oxygen (HBO2) for the treatment of ISSHL, including eight randomized controlled trials. The best and most consistent results are obtained when HBO2 is initiated within two weeks of symptom onset and combined with corticosteroid treatment. The average hearing gain is 19.3 dB for moderate hearing loss and 37.7 dB for severe cases. This improvement brings hearing deficits from the moderate/severe range into the slight/no impairment range. This is a significant gain that can markedly improve a patient's quality of life, both clinically and functionally.

  7. Oxygenation properties and isoform diversity of snake hemoglobins

    DEFF Research Database (Denmark)

    Storz, Jay F.; Natarajan, Chandrasekhar; Moriyama, Hideaki

    2015-01-01

    Available data suggest that snake hemoglobins (Hbs) are characterized by a combination of unusual structural and functional properties relative to the Hbs of other amniote vertebrates, including oxygenation-linked tetramer- dimer dissociation. However, standardized comparative data are lacking...... for snake Hbs, and the Hb isoform composition of snake red blood cells has not been systematically characterized. Here we present the results of an integrated analysis of snake Hbs and the underlying - and -type globin genes to characterize 1) Hb isoform composition of definitive erythrocytes, and 2......) the oxygenation properties of isolated isoforms as well as composite hemolysates. We used species from three families as subjects for experimental studies of Hb function: South American rattlesnake, Crotalus durissus (Viperidae); Indian python, Python molurus (Pythonidae); and yellow-bellied sea snake, Pelamis...

  8. Nitrogen and Oxygen Isotopic Studies of the Marine Nitrogen Cycle

    Science.gov (United States)

    Casciotti, Karen L.

    2016-01-01

    The marine nitrogen cycle is a complex web of microbially mediated reactions that control the inventory, distribution, and speciation of nitrogen in the marine environment. Because nitrogen is a major nutrient that is required by all life, its availability can control biological productivity and ecosystem structure in both surface and deep-ocean communities. Stable isotopes of nitrogen and oxygen in nitrate and nitrite have provided new insights into the rates and distributions of marine nitrogen cycle processes, especially when analyzed in combination with numerical simulations of ocean circulation and biogeochemistry. This review highlights the insights gained from dual-isotope studies applied at regional to global scales and their incorporation into oceanic biogeochemical models. These studies represent significant new advances in the use of isotopic measurements to understand the modern nitrogen cycle, with implications for the study of past ocean productivity, oxygenation, and nutrient status.

  9. Oxygen requirements of the earliest animals

    DEFF Research Database (Denmark)

    Mills, Daniel Brady; Ward, Lewis M.; Jones, CarriAyne;

    2014-01-01

    A rise in the oxygen content of the atmosphere and oceans is one of the most popular explanations for the relatively late and abrupt appearance of animal life on Earth. In this scenario, Earth's surface environment failed to meet the high oxygen requirements of animals up until the middle to late...... Neoproterozoic Era (850-542 million years ago), when oxygen concentrations sufficiently rose to permit the existence of animal life for the first time. Although multiple lines of geochemical evidence support an oxygenation of the Ediacaran oceans (635-542 million years ago), roughly corresponding with the first...... appearance of metazoans in the fossil record, the oxygen requirements of basal animals remain unclear. Here we show that modern demosponges, serving as analogs for early animals, can survive under low-oxygen conditions of 0.5-4.0% present atmospheric levels. Because the last common ancestor of metazoans...

  10. Aerobic growth at nanomolar oxygen concentrations

    DEFF Research Database (Denmark)

    Stolper, Daniel; Revsbech, Niels Peter; Canfield, Donald Eugene

    2010-01-01

    known. These capabilities also provide a framework for reconstructing a critical period in the history of life, because low, but not negligible, atmospheric oxygen levels could have persisted before the "Great Oxidation" of the Earth's surface about 2.3 to 2.4 billion years ago. Here, we show......Molecular oxygen (O2) is the second most abundant gas in the Earth's atmosphere, but in many natural environments, its concentration is reduced to low or even undetectable levels. Although low-oxygen-adapted organisms define the ecology of low-oxygen environments, their capabilities are not fully...... that Escherichia coli K-12, chosen for its well-understood biochemistry, rapid growth rate, and low-oxygen-affinity terminal oxidase, grows at oxygen levels of ≤ 3 nM, two to three orders of magnitude lower than previously observed for aerobes. Our study expands both the environmental range and temporal history...

  11. Aerobic growth at nanomolar oxygen concentrations

    DEFF Research Database (Denmark)

    Stolper, Daniel Aaron; Revsbech, Niels Peter; Canfield, Donald Eugene

    2010-01-01

    known. These capabilities also provide a framework for reconstructing a critical period in the history of life, because low, but not negligible, atmospheric oxygen levels could have persisted before the “Great Oxidation” of the Earth’s surface about 2.3 to 2.4 billion years ago. Here, we show......Molecular oxygen (O2) is the second most abundant gas in the Earth’s atmosphere, but in many natural environments, its concentration is reduced to low or even undetectable levels. Although low-oxygen-adapted organisms define the ecology of low-oxygen environments, their capabilities are not fully...... that Escherichia coli K-12, chosen for its well-understood biochemistry, rapid growth rate, and low-oxygen-affinity terminal oxidase, grows at oxygen levels of ≤ 3 nM, two to three orders of magnitude lower than previously observed for aerobes. Our study expands both the environmental range and temporal history...

  12. A survey of alternative oxygen production technologies

    Science.gov (United States)

    Lueck, Dale E.; Parrish, Clyde F.; Buttner, William J.; Surma, Jan M.

    2001-02-01

    Utilization of the Martian atmosphere for the production of fuel and oxygen has been extensively studied. The baseline fuel production process is a Sabatier reactor, which produces methane and water from carbon dioxide and hydrogen. The oxygen produced from the electrolysis of the water is only half of that needed for methane-based rocket propellant, and additional oxygen is needed for breathing air, fuel cells and other energy sources. Zirconia electrolysis cells for the direct reduction of CO2 are being developed as an alternative means of producing oxygen, but present many challenges for a large-scale oxygen production system. The very high operating temperatures and fragile nature of the cells coupled with fairly high operating voltages leave room for improvement. This paper will survey alternative oxygen production technologies, present data on operating characteristics, materials of construction, and some preliminary laboratory results on attempts to implement each. .

  13. Oxygen diffusion in bilayer polymer films

    DEFF Research Database (Denmark)

    Poulsen, Lars; Zebger, Ingo; Tofte, Jannik Pentti;

    2004-01-01

    Experiments to quantify oxygen diffusion have been performed on polymer samples in which a film of poly(ethylene-co-norbornene) was cast onto a film of polystyrene which, in turn, was cast onto an oxygen-impermeable substrate. In the technique employed, the time evolution of oxygen transport...... through the film of poly(ethylene-co-norbornene) and into the polystyrene film was monitored using the phosphorescence of singlet oxygen as a spectroscopic probe. To analyze the data, it was necessary to solve Fick's second law of diffusion for both polymer films. Tractable analytical and numerical...... solutions were obtained for the problem. Moreover, the numerical solution is sufficiently general that it can be used to simulate oxygen concentration profiles in films consisting of more than two layers. Data obtained from the bilayer films yield a diffusion coefficient for oxygen in poly...

  14. Methodology for the assessment of oxygen as an energy carrier

    Science.gov (United States)

    Yang, Ming Wei

    Due to the energy intensity of the oxygen generating process, the electric power grid would benefit if the oxygen generating process was consumed electric power only during low demand periods. Thus, the question to be addressed in this study is whether oxygen production and/or usage can be modified to achieve energy storage and/or transmission objectives at lower cost. The specific benefit to grid would be a leveling, over time, of the demand profile and thus would require less installation capacity. In order to track the availability of electricity, a compressed air storage unit is installed between the cryogenic distillation section and the main air compressor of air separation unit. A profit maximizing scheme for sizing storage inventory and related equipments is developed. The optimum scheme is capable of market responsiveness. Profits of steel maker, oxy-combustion, and IGCC plants with storage facilities can be higher than those plants without storage facilities, especially, at high-price market. Price tracking feature of air storage integration will certainly increase profit margins of the plants. The integration may push oxy-combustion and integrated gasification combined cycle process into economic viability. Since oxygen is used in consumer sites, it may generate at remote locations and transport to the place needed. Energy losses and costs analysis of oxygen transportation is conducted for various applications. Energy consumptions of large capacity and long distance GOX and LOX pipelines are lower than small capacity pipelines. However, transportation losses and costs of GOX and LOX pipelines are still higher than electricity transmission.

  15. Effect of epidural blockade and oxygen therapy on changes in subcutaneous oxygen tension after abdominal surgery

    DEFF Research Database (Denmark)

    Rosenberg, J; Pedersen, U; Erichsen, C J

    1994-01-01

    oxygen tension, arterial oxygen saturation, heart rate, and skin temperature on the day after operation, and arterial blood for gas analysis was drawn every 15 min during the study. A fluid challenge (10 ml saline/kg body wt) did not alter any of the measured values. The epidural blockade did not change...... any of the measured values. Oxygen therapy before epidural blockade increased median subcutaneous oxygen tension from 60 to 71 mmHg (P tension with oxygen therapy was 30 (15-55) min...... without epidural blockade and 15 (10-20) min with blockade (P tension with or without oxygen therapy after elective uncomplicated major abdominal surgery....

  16. Blood oxygen content in microliter samples using an easy-to-build galvanic oxygen cell.

    Science.gov (United States)

    Grubb, B R; Mills, C D

    1981-02-01

    We have designed a simple, inexpensive, easy-to-build and operate apparatus for measuring blood oxygen content. The galvanic oxygen cell (fuel cell) requires as little as 1 microliter of blood and has a measuring time of 1-3 min. It is well suited for measuring oxygen content in fluids low in oxygen inasmuch as the sensitivity of the instrument is variable. Either air or water (at a known temperature and oxygen tension) can be used for calibration. No significant differences in blood oxygen content measured with our cell or the Van Slyke manometric method were found.

  17. Spatial Variations in Vitreous Oxygen Consumption.

    Science.gov (United States)

    Murali, Karthik; Kang, Dongyang; Nazari, Hossein; Scianmarello, Nicholas; Cadenas, Enrique; Tai, Yu-Chong; Kashani, Amir; Humayun, Mark

    2016-01-01

    We investigated the spatial variation of vitreous oxygen consumption in enucleated porcine eyes. A custom made oxygen source was fabricated that could be localized to either the mid or posterior vitreous cavity and steady state vitreous oxygen tension was measured as a function of distance from the source using a commercially available probe. The reaction rate constant of ascorbate oxidation was estimated ex vivo by measuring the change in oxygen tension over time using vitreous harvested from porcine eyes. Vitreous ascorbate from mid and posterior vitreous was measured spectrophotometrically. When the oxygen source was placed in either the mid-vitreous (N = 6) or the posterior vitreous (N = 6), we measured a statistically significant decrease in vitreous oxygen tension as a function of distance from the oxygen source when compared to control experiments without an oxygen source; (p<0.005 for mid-vitreous and p<0.018 for posterior vitreous at all distances). The mid-vitreous oxygen tension change was significantly different from the posterior vitreous oxygen tension change at 2 and 3mm distances from the respective oxygen source (p<0.001). We also found a statistically significant lower concentration of ascorbate in the mid-vitreous as compared to posterior vitreous (p = 0.02). We determined the reaction rate constant, k = 1.61 M(-1) s(-1) ± 0.708 M(-1) s(-1) (SE), of the oxidation of ascorbate which was modeled following a second order rate equation. Our data demonstrates that vitreous oxygen consumption is higher in the posterior vitreous compared to the mid-vitreous. We also show spatial variations in vitreous ascorbate concentration.

  18. Oxygen equilibrium of brachiopod Lingula hemerythrin.

    Science.gov (United States)

    MANWELL, C

    1960-08-26

    In contrast to hemerythrin from five different species of sipunculid worms, ecardine brachiopod Lingula hemerythrin has an oxygen equilibrium which is reversibly altered by pH changes, both the oxygen affinity (Bohr effect) and the interactions between oxygen-binding centers being a function of pH. The significance of these phenomena is discussed in view of the phylogenetic distribution of hemerythrin and the function of respiratory pigments.

  19. Oxygen absorbers in food preservation: a review

    OpenAIRE

    Cichello, Simon Angelo

    2014-01-01

    The preservation of packaged food against oxidative degradation is essential to establish and improve food shelf life, customer acceptability, and increase food security. Oxygen absorbers have an important role in the removal of dissolved oxygen, preserving the colour, texture and aroma of different food products, and importantly inhibition of food spoilage microbes. Active packaging technology in food preservation has improved over decades mostly due to the sealing of foods in oxygen imperme...

  20. Oxygen Reperfusion Damage in an Insect

    OpenAIRE

    2007-01-01

    The deleterious effects of anoxia followed by reperfusion with oxygen in higher animals including mammals are well known. A convenient and genetically well characterized small-animal model that exhibits reproducible, quantifiable oxygen reperfusion damage is currently lacking. Here we describe the dynamics of whole-organism metabolic recovery from anoxia in an insect, Drosophila melanogaster, and report that damage caused by oxygen reperfusion can be quantified in a novel but straightforward ...

  1. Tissue oxygen monitoring by photoacoustic lifetime imaging (PALI) and its application to image-guided photodynamic therapy (PDT)

    Science.gov (United States)

    Shao, Qi; Morgounova, Ekaterina; Ashkenazi, Shai

    2015-03-01

    The oxygen partial pressure (pO2), which results from the balance between oxygen delivery and its consumption, is a key component of the physiological state of a tissue. Images of oxygen distribution can provide essential information for identifying hypoxic tissue and optimizing cancer treatment. Previously, we have reported a noninvasive in vivo imaging modality based on photoacoustic lifetime. The technique maps the excited triplet state of oxygen-sensitive dye, thus reflects the spatial and temporal distribution of tissue oxygen. We have applied PALI on tumor on small animals to identify hypoxia area. We also showed that PALI is able monitor changes of tissue oxygen, in an acute ischemia and breathing modulation model. Here we present our work on developing a treatment/imaging modality (PDT-PALI) that integrates PDT and a combined ultrasound/photoacoustic imaging system. The system provides real-time feedback of three essential parameters namely: tissue oxygen, light penetration in tumor location, and distribution of photosensitizer. Tissue oxygen imaging is performed by applying PALI, which relies on photoacoustic probing of oxygen-dependent, excitation lifetime of Methylene Blue (MB) photosensitizer. Lifetime information can also be used to generate image showing the distribution of photosensitizer. The level and penetration depth of PDT illumination can be deduced from photoacoustic imaging at the same wavelength. All images will be combined with ultrasound B-mode images for anatomical reference.

  2. Transcutaneous oxygen tension in imminent foot gangrene

    DEFF Research Database (Denmark)

    Tønnesen, K H

    1978-01-01

    with moderate obstruction, the oxygen tension reached zero at a toe systolic blood pressure of 5--10 mmHg (tilt toe up) and reached arterial oxygen tension at about 50 to 70 mmHg (tilt toe down). In legs withsevere arterial obstruction and ischaemic rest pain, oxygen tension rose from zero not before systolic......Transcutaneous oxygen tension at 44 degree C and maximal isotope clearance (90m Tc-pretechnetate + histramine) just proximal to the 1st toe and systolic toe blood pressure (strain gauge) were studied on a tilt table in patients with various degrees of obstructive arteriosclerotic disease. In legs...

  3. Optimal oxygen saturation in premature infants

    Directory of Open Access Journals (Sweden)

    Meayoung Chang

    2011-09-01

    Full Text Available There is a delicate balance between too little and too much supplemental oxygen exposure in premature infants. Since underuse and overuse of supplemental oxygen can harm premature infants, oxygen saturation levels must be monitored and kept at less than 95% to prevent reactive oxygen species-related diseases, such as retinopathy of prematurity and bronchopulmonary dysplasia. At the same time, desaturation below 80 to 85% must be avoided to prevent adverse consequences, such as cerebral palsy. It is still unclear what range of oxygen saturation is appropriate for premature infants; however, until the results of further studies are available, a reasonable target for pulse oxygen saturation (SpO2 is 90 to 93% with an intermittent review of the correlation between SpO2 and the partial pressure of arterial oxygen tension (PaO2. Because optimal oxygenation depends on individuals at the bedside making ongoing adjustments, each unit must define an optimal target range and set alarm limits according to their own equipment or conditions. All staff must be aware of these values and adjust the concentration of supplemental oxygen frequently.

  4. Oxygen, nitric oxide and articular cartilage

    Directory of Open Access Journals (Sweden)

    B Fermor

    2007-04-01

    Full Text Available Molecular oxygen is required for the production of nitric oxide (NO, a pro-inflammatory mediator that is associated with osteoarthritis and rheumatoid arthritis. To date there has been little consideration of the role of oxygen tension in the regulation of nitric oxide production associated with arthritis. Oxygen tension may be particularly relevant to articular cartilage since it is avascular and therefore exists at a reduced oxygen tension. The superficial zone exists at approximately 6% O2, while the deep zone exists at less than 1% O2. Furthermore, oxygen tension can alter matrix synthesis, and the material properties of articular cartilage in vitro.The increase in nitric oxide associated with arthritis can be caused by pro-inflammatory cytokines and mechanical stress. Oxygen tension significantly alters endogenous NO production in articular cartilage, as well as the stimulation of NO in response to both mechanical loading and pro-inflammatory cytokines. Mechanical loading and pro-inflammatory cytokines also increase the production of prostaglandin E2 (PGE2. There is a complex interaction between NO and PGE2, and oxygen tension can alter this interaction. These findings suggest that the relatively low levels of oxygen within the joint may have significant influences on the metabolic activity, and inflammatory response of cartilage as compared to ambient levels. A better understanding of the role of oxygen in the production of inflammatory mediators in response to mechanical loading, or pro-inflammatory cytokines, may aid in the development of strategies for therapeutic intervention in arthritis.

  5. Identification of an Archean marine oxygen oasis

    Energy Technology Data Exchange (ETDEWEB)

    Riding, Dr Robert E [University of Tennessee (UT); Fralick, Dr Philip [Lakehead University, Canada; Liang, Liyuan [ORNL

    2014-01-01

    The early Earth was essentially anoxic. A number of indicators suggest the presence of oxygenic photosynthesis 2700 3000 million years (Ma) ago, but direct evidence for molecular oxygen (O2) in seawater has remained elusive. Here we report rare earth element (REE) analyses of 2800 million year old shallowmarine limestones and deep-water iron-rich sediments at Steep Rock Lake, Canada. These show that the seawater from which extensive shallow-water limestones precipitated was oxygenated, whereas the adjacent deeper waters where iron-rich sediments formed were not. We propose that oxygen promoted limestone precipitation by oxidative removal of dissolved ferrous iron species, Fe(II), to insoluble Fe(III) oxyhydroxide, and estimate that at least 10.25 M oxygen concentration in seawater was required to accomplish this at Steep Rock. This agrees with the hypothesis that an ample supply of dissolved Fe(II) in Archean oceans would have hindered limestone formation. There is no direct evidence for the oxygen source at Steep Rock, but organic carbon isotope values and diverse stromatolites in the limestones suggest the presence of cyanobacteria. Our findings support the view that during the Archean significant oxygen levels first developed in protected nutrient-rich shallow marine habitats. They indicate that these environments were spatially restricted, transient, and promoted limestone precipitation. If Archean marine limestones in general reflect localized oxygenic removal of dissolved iron at the margins of otherwise anoxic iron-rich seas, then early oxygen oases are less elusive than has been assumed.

  6. Early oxygen-utilization and brain activity in preterm infants.

    Directory of Open Access Journals (Sweden)

    Maria Luisa Tataranno

    Full Text Available The combined monitoring of oxygen supply and delivery using Near-InfraRed spectroscopy (NIRS and cerebral activity using amplitude-integrated EEG (aEEG could yield new insights into brain metabolism and detect potentially vulnerable conditions soon after birth. The relationship between NIRS and quantitative aEEG/EEG parameters has not yet been investigated. Our aim was to study the association between oxygen utilization during the first 6 h after birth and simultaneously continuously monitored brain activity measured by aEEG/EEG. Forty-four hemodynamically stable babies with a GA < 28 weeks, with good quality NIRS and aEEG/EEG data available and who did not receive morphine were included in the study. aEEG and NIRS monitoring started at NICU admission. The relation between regional cerebral oxygen saturation (rScO2 and cerebral fractional tissue oxygen extraction (cFTOE, and quantitative measurements of brain activity such as number of spontaneous activity transients (SAT per minute (SAT rate, the interval in seconds (i.e. time between SATs (ISI and the minimum amplitude of the EEG in μV (min aEEG were evaluated. rScO2 was negatively associated with SAT rate (β=-3.45 [CI=-5.76- -1.15], p=0.004 and positively associated with ISI (β=1.45 [CI=0.44-2.45], p=0.006. cFTOE was positively associated with SAT rate (β=0.034 [CI=0.009-0.059], p=0.008 and negatively associated with ISI (β=-0.015 [CI=-0.026- -0.004], p=0.007. Oxygen delivery and utilization, as indicated by rScO2 and cFTOE, are directly related to functional brain activity, expressed by SAT rate and ISI during the first hours after birth, showing an increase in oxygen extraction in preterm infants with increased early electro-cerebral activity. NIRS monitored oxygenation may be a useful biomarker of brain vulnerability in high-risk infants.

  7. Insulating ferromagnetic oxide films: the controlling role of oxygen vacancy ordering

    Energy Technology Data Exchange (ETDEWEB)

    Salafranca Laforga, Juan I [ORNL; Salafranca, Juan [Universidad Complutense de Madrid, Spain; Biskup, Nevenko [ORNL; Mehta, Virat [University of California, Berkeley; Oxley, Mark P [ORNL; Suzuki, Yuri [Stanford University; Pennycook, Stephen J [University of Tennessee, Knoxville (UTK); Pantelides, Sokrates T. [Vanderbilt University, Nashville; Varela del Arco, Maria [ORNL

    2014-01-01

    The origin of ferromagnetism in strained epitaxial LaCoO3 films has been a long-standing mystery. Here, we combine atomically resolved Z-contrast imaging, electron-energy-loss spectroscopy, and density-functional calculations to demonstrate that, in epitaxial LaCoO3 films, oxygen-vacancy superstructures release strain, control the film s electronic properties, and produce the observed ferromagnetism via the excess electrons in the Co d states. Although oxygen vacancies typically dope a material n-type, we find that ordered vacancies induce Peierls-like minigaps which, combined with strain relaxation, trigger a nonlinear rupture of the energy bands, resulting in insulating behavior.

  8. Mitigation strategies of intergranular corrosion in systems of reactors of water boiling (BWR). Combined action of the chemistry of the hydrogen and the oxygen; Estrategias de mitigacion de la corrosion intergranular en sistemas de reactores de agua en ebullicion (BWR). Accion combinada de la quimica del hidrogeno y del oxigeno

    Energy Technology Data Exchange (ETDEWEB)

    Verdugo, M.

    2015-07-01

    Inter-Granular Stress Corrosion cracking (IGSCC) in austenitic stainless steel and in austenitic nickel-based alloys has been the subject of many studies the aim of which was to resolve one of the main problems faced by BWR nuclear power plants since the 1960s. This corrosion phenomenon is the result of the combined action of three factors: sensitization of the material, high local stresses and an aggressive medium. This paper deals with these factors separately and analyzes the oxidative chemistry of BWR reactors (aggressivity of the medium) as one the main causes if IGSCC. (Author)

  9. IMPACT OF OXYGENATED FUEL ON DIESEL ENGINE PERFORMANCE AND EMISSIONS

    Energy Technology Data Exchange (ETDEWEB)

    Boehman, Andre L.

    2000-08-20

    As evidenced by recent lawsuits brought against operators of large diesel truck fleets [1] and by the Consent Decree brought against the heavy-duty diesel manufacturers [2], the environmental and health effects of diesel engine emissions continue to be a significant concern. Reduction of diesel engine emissions has traditionally been achieved through a combination of fuel system, combustion chamber, and engine control modifications [3]. Catalytic aftertreatment has become common on modern diesel vehicles, with the predominant device being the diesel oxidation catalytic converter [3]. To enable advanced after-treatment devices and to directly reduce emissions, significant recent interest has focused on reformulation of diesel fuel, particularly the reduction of sulfur content. The EPA has man-dated that diesel fuel will have only 15 ppm sulfur content by 2007, with current diesel specifications requiring around 300 ppm [4]. Reduction of sulfur will permit sulfur-sensitive aftertreatment devices, continuously regenerating particulate traps, NOx control catalysts, and plasma assisted catalysts to be implemented on diesel vehicles [4]. Another method of reformulating diesel fuel to reduce emissions is to incorporate oxygen in the fuel, as was done in the reformulation of gasoline. The use of methyl tertiary butyl ether (MTBE) in reformulated gasoline has resulted in contamination of water resources across the country [5]. Nonetheless, by relying on the lessons learned from MTBE, oxygenation of diesel fuel may be accomplished without compromising water quality. Oxygenation of diesel fuel offers the possibility of reducing particulate matter emissions significantly, even for the current fleet of diesel vehicles. The mechanism by which oxygen content leads to particulate matter reductions is still under debate, but recent evidence shows clearly that ''smokeless'' engine operation is possible when the oxygen content of diesel fuel reaches roughly 38% by

  10. The effect of oxygen tension on human articular chondrocyte matrix synthesis: integration of experimental and computational approaches.

    Science.gov (United States)

    Li, S; Oreffo, R O C; Sengers, B G; Tare, R S

    2014-09-01

    Significant oxygen gradients occur within tissue engineered cartilaginous constructs. Although oxygen tension is an important limiting parameter in the development of new cartilage matrix, its precise role in matrix formation by chondrocytes remains controversial, primarily due to discrepancies in the experimental setup applied in different studies. In this study, the specific effects of oxygen tension on the synthesis of cartilaginous matrix by human articular chondrocytes were studied using a combined experimental-computational approach in a "scaffold-free" 3D pellet culture model. Key parameters including cellular oxygen uptake rate were determined experimentally and used in conjunction with a mathematical model to estimate oxygen tension profiles in 21-day cartilaginous pellets. A threshold oxygen tension (pO2 ≈ 8% atmospheric pressure) for human articular chondrocytes was estimated from these inferred oxygen profiles and histological analysis of pellet sections. Human articular chondrocytes that experienced oxygen tension below this threshold demonstrated enhanced proteoglycan deposition. Conversely, oxygen tension higher than the threshold favored collagen synthesis. This study has demonstrated a close relationship between oxygen tension and matrix synthesis by human articular chondrocytes in a "scaffold-free" 3D pellet culture model, providing valuable insight into the understanding and optimization of cartilage bioengineering approaches.

  11. Decline in global oceanic oxygen content during the past five decades

    Science.gov (United States)

    Schmidtko, Sunke; Stramma, Lothar; Visbeck, Martin

    2017-02-01

    Ocean models predict a decline in the dissolved oxygen inventory of the global ocean of one to seven per cent by the year 2100, caused by a combination of a warming-induced decline in oxygen solubility and reduced ventilation of the deep ocean. It is thought that such a decline in the oceanic oxygen content could affect ocean nutrient cycles and the marine habitat, with potentially detrimental consequences for fisheries and coastal economies. Regional observational data indicate a continuous decrease in oceanic dissolved oxygen concentrations in most regions of the global ocean, with an increase reported in a few limited areas, varying by study. Prior work attempting to resolve variations in dissolved oxygen concentrations at the global scale reported a global oxygen loss of 550 ± 130 teramoles (1012 mol) per decade between 100 and 1,000 metres depth based on a comparison of data from the 1970s and 1990s. Here we provide a quantitative assessment of the entire ocean oxygen inventory by analysing dissolved oxygen and supporting data for the complete oceanic water column over the past 50 years. We find that the global oceanic oxygen content of 227.4 ± 1.1 petamoles (1015 mol) has decreased by more than two per cent (4.8 ± 2.1 petamoles) since 1960, with large variations in oxygen loss in different ocean basins and at different depths. We suggest that changes in the upper water column are mostly due to a warming-induced decrease in solubility and biological consumption. Changes in the deeper ocean may have their origin in basin-scale multi-decadal variability, oceanic overturning slow-down and a potential increase in biological consumption.

  12. Oxygen Sensing Difluoroboron β-Diketonate Polylactide Materials with Tunable Dynamic Ranges for Wound Imaging.

    Science.gov (United States)

    DeRosa, Christopher A; Seaman, Scott A; Mathew, Alexander S; Gorick, Catherine M; Fan, Ziyi; Demas, James N; Peirce, Shayn M; Fraser, Cassandra L

    2016-11-23

    Difluoroboron β-diketonate poly(lactic acid) materials exhibit both fluorescence (F) and oxygen sensitive room-temperature phosphorescence (RTP). Introduction of halide heavy atoms (Br and I) is an effective strategy to control the oxygen sensitivity in these materials. A series of naphthyl-phenyl (nbm) dye derivatives with hydrogen, bromide and iodide substituents were prepared for comparison. As nanoparticles, the hydrogen derivative was hypersensitive to oxygen (0-0.3%), while the bromide analogue was suited for hypoxia detection (0-3% O2). The iodo derivative, BF2nbm(I)PLA, showed excellent F to RTP peak separation and an 0-100% oxygen sensitivity range unprecedented for metal-free RTP emitting materials. Due to the dual emission and unconventionally long RTP lifetimes of these O2 sensing materials, a portable, cost-effective camera was used to quantify oxygen levels via lifetime and red/green/blue (RGB) ratiometry. The hypersensitive H dye was well matched to lifetime detection, simultaneous lifetime and ratiometric imaging was possible for the bromide analogue, whereas the iodide material, with intense RTP emission and a shorter lifetime, was suited for RGB ratiometry. To demonstrate the prospects of this camera/material design combination for bioimaging, iodide boron dye-PLA nanoparticles were applied to a murine wound model to detect oxygen levels. Surprisingly, wound oxygen imaging was achieved without covering (i.e. without isolating from ambient conditions, air). Additionally, would healing was monitored via wound size reduction and associated oxygen recovery, from hypoxic to normoxic. These single-component materials provide a simple tunable platform for biological oxygen sensing that can be deployed to spatially resolve oxygen in a variety of environments.

  13. Effects of oxygen concentration on atmospheric pressure dielectric barrier discharge in Argon-Oxygen Mixture

    Science.gov (United States)

    Li, Xuechun; Li, Dian; Wang, Younian

    2016-09-01

    A dielectric barrier discharge (DBD) can generate a low-temperature plasma easily at atmospheric pressure and has been investigated for applications in trials in cancer therapy, sterilization, air pollution control, etc. It has been confirmed that reactive oxygen species (ROS) play a key role in the processes. In this work, we use a fluid model to simulate the plasma characteristics for DBD in argon-oxygen mixture. The effects of oxygen concentration on the plasma characteristics have been discussed. The evolution mechanism of ROS has been systematically analyzed. It was found that the ground state oxygen atoms and oxygen molecular ions are the dominated oxygen species under the considered oxygen concentrations. With the oxygen concentration increasing, the densities of electrons, argon atomic ions, resonance state argon atoms, metastable state argon atoms and excited state argon atoms all show a trend of decline. The oxygen molecular ions density is high and little influenced by the oxygen concentration. Ground state oxygen atoms density tends to increase before falling. The ozone density increases significantly. Increasing the oxygen concentration, the discharge mode begins to change gradually from the glow discharge mode to Townsend discharge mode. Project supported by the National Natural Science Foundation of China (Grant No. 11175034).

  14. Solar Energy Systems for Lunar Oxygen Generation

    Science.gov (United States)

    Colozza, Anthony J.; Heller, Richard S.; Wong, Wayne A.; Hepp, Aloysius F.

    2010-01-01

    An evaluation of several solar concentrator-based systems for producing oxygen from lunar regolith was performed. The systems utilize a solar concentrator mirror to provide thermal energy for the oxygen production process. Thermal energy to power a Stirling heat engine and photovoltaics are compared for the production of electricity. The electricity produced is utilized to operate the equipment needed in the oxygen production process. The initial oxygen production method utilized in the analysis is hydrogen reduction of ilmenite. Utilizing this method of oxygen production a baseline system design was produced. This baseline system had an oxygen production rate of 0.6 kg/hr with a concentrator mirror size of 5 m. Variations were performed on the baseline design to show how changes in the system size and process (rate) affected the oxygen production rate. An evaluation of the power requirements for a carbothermal lunar regolith reduction reactor has also been conducted. The reactor had a total power requirement between 8,320 to 9,961 W when producing 1000 kg/year of oxygen. The solar concentrator used to provide the thermal power (over 82 percent of the total energy requirement) would have a diameter of less than 4 m.

  15. Atmospheric oxygenation three billion years ago

    DEFF Research Database (Denmark)

    Crowe, Sean; Døssing, Lasse Nørbye; Beukes, Nicolas J.;

    2013-01-01

    It is widely assumedthat atmospheric oxygen concentrations remained persistently low (less than 1025 timespresent levels) for about the first 2 billion years of Earth’s history1. The first long-term oxygenation of the atmosphere is thought tohave taken place around2.3 billion years ago, during th...

  16. Oxygen partial pressure control for microgravity experiments

    OpenAIRE

    Schulz, Michael; Brillo, Jürgen; Stenzel, Christian; Fritze, Holger

    2012-01-01

    A system consisting of a high-temperature yttrium-stabilized zirconia (YSZ) based oxygen ion pump and potentiometric sensor enables precise measurement and control of oxygen partial pressure, pO2, at elevated temperatures within 0.2 to 10^-20 bar.

  17. Oxygen Effects in Anaerobic Digestion - II

    Directory of Open Access Journals (Sweden)

    Deshai Botheju

    2010-04-01

    Full Text Available Standard models describing bio-gasification using anaerobic digestion do not include necessary processes to describe digester dynamics under the conditions of oxygen presence. Limited oxygenation in anaerobic digestion can sometimes be beneficial. The oxygen effects included anaerobic digestion model, ADM 1-Ox, was simulated against experimental data obtained from laboratory scale anaerobic digesters operated under different oxygenation conditions. ADM 1-Ox predictions are generally in good agreement with the trends of the experimental data. ADM 1-Ox simulations suggest the existence of an optimum oxygenation level corresponding to a peak methane yield. The positive impact of oxygenation on methane yield is more pronounced at conditions characterized by low hydrolysis rate coefficients (slowly degradable feed and low biomass concentrations. The optimum oxygenation point moves towards zero when the hydrolysis rate coefficient and the biomass concentration increase. Accordingly, the impact of oxygenation on methane yield can either be positive or negative depending on the digestion system characteristics. The developed ADM 1-Ox model can therefore be a valuable tool for recognizing suitable operating conditions for achieving the maximum benefits from partial aeration in anaerobic digestion.

  18. Hyperbaric oxygen therapy improves colorectal anastomotic healing

    NARCIS (Netherlands)

    G.S.A. Boersema (Geesien); Z. Wu (Zhouqiao); L.F. Kroese; S. Vennix (Sandra); Y.M. Bastiaansen-Jenniskens (Yvonne); J.W. van Neck (Han); K.H. Lam; G.J. Kleinrensink (Gert Jan); J. Jeekel (Johannes); J.F. Lange (Johan F.)

    2016-01-01

    textabstractPurpose: Hyperbaric oxygen treatment (HBOT) has been found to improve the healing of poorly oxygenated tissues. This study aimed to investigate the influence of HBOT on the healing in ischemic colorectal anastomosis. Methods: Forty Wistar rats were randomly divided into a treatment group

  19. Oxygen absorbers in food preservation: a review.

    Science.gov (United States)

    Cichello, Simon Angelo

    2015-04-01

    The preservation of packaged food against oxidative degradation is essential to establish and improve food shelf life, customer acceptability, and increase food security. Oxygen absorbers have an important role in the removal of dissolved oxygen, preserving the colour, texture and aroma of different food products, and importantly inhibition of food spoilage microbes. Active packaging technology in food preservation has improved over decades mostly due to the sealing of foods in oxygen impermeable package material and the quality of oxygen absorber. Ferrous iron oxides are the most reliable and commonly used oxygen absorbers within the food industry. Oxygen absorbers have been transformed from sachets of dried iron-powder to simple self-adhesive patches to accommodate any custom size, capacity and application. Oxygen concentration can be effectively lowered to 100 ppm, with applications spanning a wide range of food products and beverages across the world (i.e. bread, meat, fish, fruit, and cheese). Newer molecules that preserve packaged food materials from all forms of degradation are being developed, however oxygen absorbers remain a staple product for the preservation of food and pharmaceutical products to reduce food wastage in developed nations and increased food security in the developing & third world.

  20. 76 FR 12550 - Lavatory Oxygen Systems

    Science.gov (United States)

    2011-03-08

    ... impact on safety. The ARAC found that the frequency of occurrences necessitating the use of oxygen was... regulations pertaining to supplemental oxygen systems. This SFAR also permits manufacturers and modifiers of.... 3507(d)) requires that the FAA consider the impact of paperwork and other information...

  1. Oxygen electrode in molten carbonate fuel cells

    Science.gov (United States)

    Dave, B. B.; White, R. E.; Srinivasan, S.; Appleby, A. J.

    1990-12-01

    During this quarter, impedance data were analyzed for an oxygen reduction process in molten carbonate electrolyte and a manuscript, Impedance Analysis for Oxygen Reduction in a Lithium Carbonate Melt: Effects of Partial Pressure of Carbon Dioxide and Temperature, was prepared to be submitted to Journal of the Electrochemical Society for publication.

  2. Scheele's Priority for the Discovery of Oxygen

    Science.gov (United States)

    Cassebaum, H.; Schufle, J. A.

    1975-01-01

    Concludes that Carl Scheele first observed oxygen and clearly understood what he was observing in June 1771, when he heated manganese dioxide with concentrated sulfuric acid. This was more than three years before Lavoisier or Priestley (who is usually credited with the discovery of oxygen) made similar observations. (Author/MLH)

  3. A rechargeable carbon-oxygen battery

    DEFF Research Database (Denmark)

    2014-01-01

    The invention relates to a rechargeable battery and a method to operate a rechargeable battery having high efficiency and high energy density for storing energy. The battery stores electrical energy in the bonds of carbon and oxygen atoms by converting carbon dioxide into solid carbon and oxygen....

  4. KINETICS OF DELIGNIFICATION AND CARBOHYDRATE DEGRADATION DURING OXYGEN BLEACHING

    Institute of Scientific and Technical Information of China (English)

    K. L Nguyen

    2004-01-01

    Carbohydrate degradation during oxygen bleaching is associated with cleavage reactions. It is apparent that the loss of the cellulose DP (degree ofpolymisation)is strongly affected by the extent of the delignification. A strong linear correlation can be established between the DP of cellulose chains and the residual lignin in the pulp. The Nuclear Growth concept and Percolation Theory for heterogenous system can be combined to formulate kinetic models for both the delignification and the degradation of carbohydrate. The models prediction is statistically robust and can be applied to different pulps at different bleaching conditions.

  5. A case of vertebrobasilar stroke during oxygen-ozone therapy.

    Science.gov (United States)

    Corea, Francesco; Amici, Serena; Murgia, Nicola; Tambasco, Nicola

    2004-01-01

    Despite only sporadic observations, the use of medical oxygen-ozone therapy is a largely diffused treatment for lumbar disk herniation that has failed to respond to conservative management. Combined intradiscal and periganglionic injection of medical ozone and periganglionic injection of steroids are presumed to have a cumulative effect enhancing the overall outcome of treatment for pain caused by disk herniation. To our knowledge, this is the first reported case of stroke during such medical application. The patient had Anton's syndrome as a result of top of the basilar hypoperfusion.

  6. Some Applications of Fast Neutron Activation Analysis of Oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Owrang, Farshid

    2003-07-01

    In this thesis we focus on applications of neutron activation of oxygen for several purposes: A) measuring the water level in a laboratory tank, B) measuring the water flow in a pipe system set-up, C) analysing the oxygen in combustion products formed in a modern gasoline SI engine, and D) measuring on-line the amount of oxygen in bulk liquids. A) Water level measurements. The purpose of this work was to perform radiation based water level measurements, aimed at nuclear reactor vessels, on a laboratory scale. A laboratory water tank was irradiated by fast neutrons from a neutron generator. The water was activated at different water levels and the water level was decreased. The produced gamma radiation was measured using two detectors at different heights. The results showed that the method is suitable for measurement of water level and that a relatively small experimental set-up can be used for developing methods for water level measurements in real boiling water reactors based on activated oxygen in the water. B) Water flows in pipe. The goal in this work was to investigate the asymmetric distribution of activity in flow measurements with pulsed neutron activation (PNA) in a laboratory piping system. Earlier investigations had shown a discrepancy between the measured velocity of the activated water by PNA and the true mean velocity in the pipe. This discrepancy decreased with larger distances from the activation point. It was speculated that the induced activity in the pipe did not distribute homogeneously. With inhomogeneous radial distribution of activity in combination with a velocity profile in the pipe, the activated water may not have the same velocity as the mean velocity of water in the pipe. To study this phenomenon, a water-soluble colour was injected into a transparent pipe for simulation of the transport of the activated water. The radial concentration of the colour, at different distances from the activation point, was determined. The result

  7. Oxygen Absorption in Cooling Flows.

    Science.gov (United States)

    Buote

    2000-04-01

    The inhomogeneous cooling flow scenario predicts the existence of large quantities of gas in massive elliptical galaxies, groups, and clusters that have cooled and dropped out of the flow. Using spatially resolved, deprojected X-ray spectra from the ROSAT PSPC, we have detected strong absorption over energies approximately 0.4-0.8 keV intrinsic to the central approximately 1&arcmin; of the galaxy NGC 1399, the group NGC 5044, and the cluster A1795. These systems have among the largest nearby cooling flows in their respective classes and low Galactic columns. Since no excess absorption is indicated for energies below approximately 0.4 keV, the most reasonable model for the absorber is warm, collisionally ionized gas with T=105-106 K in which ionized states of oxygen provide most of the absorption. Attributing the absorption only to ionized gas reconciles the large columns of cold H and He inferred from Einstein and ASCA with the lack of such columns inferred from ROSAT and also is consistent with the negligible atomic and molecular H inferred from H i and CO observations of cooling flows. The prediction of warm ionized gas as the product of mass dropout in these and other cooling flows can be verified by Chandra and X-Ray Multimirror Mission.

  8. Ceria Based Composite Membranes for Oxygen Separation

    DEFF Research Database (Denmark)

    Gurauskis, Jonas; Ovtar, Simona; Kaiser, Andreas;

    2014-01-01

    Mixed ionic-electronic conducting membranes for oxygen gas separation are attracting a lot of interest due to their promising potential for the pure oxygen and the syngas production. Apart from the need for a sufficiently high oxygen permeation fluxes, the prolonged stability of these membranes...... under the large oxygen potential gradients at elevated temperatures is decisive for the future applications. The gadolinium doped cerium oxide (CGO) based composite membranes are considered as promising candidates due to inherent stability of CGO phase. The CGO matrix is a main oxygen ion transporter......; meanwhile the primary role of a secondary phase in this membrane is to compensate the low electronic conductivity of matrix at intended functioning conditions. In this work thin film (15-20 μm) composite membranes based on CGO matrix and LSF electronic conducting phase were fabricated and evaluated...

  9. Oxygen tension level and human viral infections.

    Science.gov (United States)

    Morinet, Frédéric; Casetti, Luana; François, Jean-Hugues; Capron, Claude; Pillet, Sylvie

    2013-09-01

    The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition.

  10. Modelling Hydrogen Reduction and Hydrodeoxygenation of Oxygenates

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Y.; Xu, Q.; Cheah, S.

    2013-01-01

    Based on Density Functional Theory (DFT) simulations, we have studied the reduction of nickel oxide and biomass derived oxygenates (catechol, guaiacol, etc.) in hydrogen. Both the kinetic barrier and thermodynamic favorability are calculated with respect to the modeled reaction pathways. In early-stage reduction of the NiO(100) surface by hydrogen, the pull-off of the surface oxygen atom and simultaneous activation of the nearby Ni atoms coordinately dissociate the hydrogen molecules so that a water molecule can be formed, leaving an oxygen vacancy on the surface. In hydrogen reaction with oxygenates catalyzed by transition metals, hydrogenation of the aromatic carbon ring normally dominates. However, selective deoxygenation is of particular interest for practical application such as biofuel conversion. Our modeling shows that doping of the transition metal catalysts can change the orientation of oxygenates adsorbed on metal surfaces. The correlation between the selectivity of reaction and the orientation of adsorption are discussed.

  11. Oxygen transfer in human carotid artery bifurcation

    Institute of Scientific and Technical Information of China (English)

    Z.G.Zhang; Y.B.Fan; X.Y.Deng

    2007-01-01

    Arterial bifurcations are places where blood flow may be disturbed and slow recirculation flow may occur.To reveal the correlation between local oxygen transfer and atherogenesis, a finite element method was employed to simulate the blood flow and the oxygen transfer in the human carotid artery bifurcation. Under steady-state flow conditions, the numerical simulation demonstrated a variation in local oxygen transfer at the bifurcation, showing that the convective condition in the disturbed flow region may produce uneven local oxygen transfer at the blood/wall interface.The disturbed blood flow with formation of slow eddies in the carotid sinus resulted in a depression in oxygen supply to the arterial wall at the entry of the sinus, which in turn may lead to an atherogenic response of the arterial wall, and contribute to the development of atherosclerotic stenosis there.

  12. Rule of oxygen transmission in dump leaching

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    According to the chemical equations, the flux and concentration of oxygen required during bacterial leaching sulfuric mineral were investigated; the rule of air bubble transmitted in granular was researched in the Dump Leaching Plant of Dexing Copper Mine. The results show that lack of oxygen in dump leaching is the critical factor of restricting leaching reaction. Pyrite is the primary oxygen-consuming mineral in bioleaching. When its content is too high, it needs a great deal of oxygen for reaction and competes for the finite oxygen with objective minerals, and thus the leaching velocity decreases greatly. The average size of ore particles and diameter of bubbles are the key parameters affecting the mass transfer coefficient. Reverse analysis was adopted, and it shows that 44.8 m3 air per unit ore can meet the requirement of production if the molar ratio of pyrite to chalcopyrite is 10.

  13. Do large predatory fish track ocean oxygenation?

    Science.gov (United States)

    Dahl, Tais W; Hammarlund, Emma U

    2011-01-01

    The Devonian appearance of 1-10 meter long armored fish (placoderms) coincides with geochemical evidence recording a transition into fully oxygenated oceans.1 A comparison of extant fish shows that the large individuals are less tolerant to hypoxia than their smaller cousins. This leads us to hypothesize that Early Paleozoic O(2) saturation levels were too low to support >1 meter size marine, predatory fish. According to a simple model, both oxygen uptake and oxygen demand scale positively with size, but the demand exceeds supply for the largest fish with an active, predatory life style. Therefore, the largest individuals may lead us to a lower limit on oceanic O(2) concentrations. Our presented model suggests 2-10 meter long predators require >30-50% PAL while smaller fish would survive at oxygen pressure acted as an evolutionary barrier for fish to grow much above ∼1 meter before the Devonian oxygenation.

  14. Electrochemical Oxygen Sensor Development for Liquid Sodium

    Science.gov (United States)

    Nollet, Billy K.

    Safe operation of a sodium-cooled fast reactor (SFR) requires in-depth understanding of the corrosion implications of liquid sodium coolant on reactor materials. Dissolved oxygen concentration is of particular importance in characterizing sodium attack, so an accurate means of measuring and controlling oxygen is crucial. There is significant room for improvement in current oxygen sensing technology, so extensive research has been conducted at the University of Wisconsin-Madison to address this issue. Experimental facilities and electrochemical oxygen sensors have been developed, tested, and analyzed. This research is discussed in detail in this report. The oxygen sensors tested in this research were developed using a yttria stabilized zirconia (YSZ) electrolyte whereas many of the past research in this field was conducted with yttria doped thoria (YDT or YST) electrolytes. Thorium, an alpha emitter, is expensive and increasingly difficult to acquire, so motivation to switch to a new material exists. YSZ is commonly used as the electrolyte for solid oxide fuel cells, and ample data is available for high temperature ionic conduction of this material. While some work has been done with YSZ in oxygen sensors (the automotive field, for example, uses YSZ O2 sensors), research on YSZ sensors in sodium is limited. A thorough study of YSZ-based electrochemical oxygen sensors must include detailed corrosion testing and analysis of YSZ in liquid sodium, careful oxygen sensor development and testing, and finally, a comprehensive analysis of the acquired sensor data. The research presented in this report describes the design and development of an electrochemical oxygen sensor for use in sodium using a YSZ electrolyte through the previously-mentioned steps. The designed sensors were subjected to a series of hypotheses which advance common understanding of oxygen sensor signal. These results were used in conjunction with past research to form reliable conclusions.

  15. Oxygen vacancy promoted methane partial oxidation over iron oxide oxygen carriers in the chemical looping process.

    Science.gov (United States)

    Cheng, Zhuo; Qin, Lang; Guo, Mengqing; Xu, Mingyuan; Fan, Jonathan A; Fan, Liang-Shih

    2016-11-30

    We perform ab initio DFT+U calculations and experimental studies of the partial oxidation of methane to syngas on iron oxide oxygen carriers to elucidate the role of oxygen vacancies in oxygen carrier reactivity. In particular, we explore the effect of oxygen vacancy concentration on sequential processes of methane dehydrogenation, and oxidation with lattice oxygen. We find that when CH4 adsorbs onto Fe atop sites without neighboring oxygen vacancies, it dehydrogenates with CHx radicals remaining on the same site and evolves into CO2via the complete oxidation pathway. In the presence of oxygen vacancies, on the other hand, the formed methyl (CH3) prefers to migrate onto the vacancy site while the H from CH4 dehydrogenation remains on the original Fe atop site, and evolves into CO via the partial oxidation pathway. The oxygen vacancies created in the oxidation process can be healed by lattice oxygen diffusion from the subsurface to the surface vacancy sites, and it is found that the outward diffusion of lattice oxygen atoms is more favorable than the horizontal diffusion on the same layer. Based on the proposed mechanism and energy profile, we identify the rate-limiting steps of the partial oxidation and complete oxidation pathways. Also, we find that increasing the oxygen vacancy concentration not only lowers the barriers of CH4 dehydrogenation but also the cleavage energy of Fe-C bonds. However, the barrier of the rate-limiting step cannot further decrease when the oxygen vacancy concentration reaches 2.5%. The fundamental insight into the oxygen vacancy effect on CH4 oxidation with iron oxide oxygen carriers can help guide the design and development of more efficient oxygen carriers and CLPO processes.

  16. Anaerobe Tolerance to Oxygen and the Potentials of Anaerobic and Aerobic Cocultures for Wastewater Treatment

    Directory of Open Access Journals (Sweden)

    M.T. Kato

    1997-12-01

    Full Text Available The anaerobic treatment processes are considered to be well-established methods for the elimination of easily biodegradable organic matter from wastewaters. Some difficulties concerning certain wastewaters are related to the possible presence of dissolved oxygen. The common belief is that anaerobes are oxygen intolerant. Therefore, the common practice is to use sequencing anaerobic and aerobic steps in separate tanks. Enhanced treatment by polishing off the residual biodegradable oxygen demand from effluents of anaerobic reactors, or the biodegradation of recalcitrant wastewater pollutants, usually requires sequenced anaerobic and aerobic bacteria activities. However, the combined activity of both bacteria can also be obtained in a single reactor. Previous experiments with either pure or mixed cultures showed that anaerobes can tolerate oxygen to a certain extent. The oxygen toxicity to methanogens in anaerobic sludges was quantified in batch experiments, as well as in anaerobic reactors. The results showed that methanogens have a high tolerance to oxygen. In practice, it was confirmed that dissolved oxygen does not constitute any detrimental effect on reactor treatment performance. This means that the coexistence of anaerobic and aerobic bacteria in one single reactor is feasible and increases the potentials of new applications in wastewater treatment

  17. Simulation studies of diesel engine performance with oxygen enriched air and water emulsified fuels

    Energy Technology Data Exchange (ETDEWEB)

    Assanis, D.N.; Baker, D. (Illinois Univ., Urbana, IL (USA)); Sekar, R.R.; Siambekos, C.T.; Cole, R.L.; Marciniak, T.J. (Argonne National Lab., IL (USA))

    1990-01-01

    A computer simulation code of a turbocharged, turbocompound diesel engine was modified to study the effects of using oxygen-enriched combustion air and water-emulsified diesel fuels. Oxygen levels of 21 percent to 40 percent by volume in the combustion air were studied. Water content in the fuel was varied from 0 percent to 50 percent mass. Simulation studies and a review and analysis of previous work in this area led to the following conclusions about expected engine performance and emissions: the power density of the engine is significantly increased by oxygen enrichment. Ignition delay and particulate emissions are reduced. Combustion temperatures and No{sub x} emissions are increased with oxygen enrichment but could be brought back to the base levels by introducing water in the fuel. The peak cylinder pressure which increases with the power output level might result in mechanical problems with engine components. Oxygen enrichment also provides an opportunity to use cheaper fuel such as No. 6 diesel fuel. Overall, the adverse effects of oxygen enrichment could be countered by the addition of water and it appears that an optimum combination of water content, oxygen level, and base diesel fuel quality may exist. This could yield improved performance and emissions characteristics compared to a state-of-the-art diesel engine. 9 refs., 8 figs.

  18. Acceleration of oxygen decline in the tropical Pacific over the past decades by aerosol pollutants

    Science.gov (United States)

    Ito, T.; Nenes, A.; Johnson, M. S.; Meskhidze, N.; Deutsch, C.

    2016-06-01

    Dissolved oxygen in the mid-depth tropical Pacific Ocean has declined in the past several decades. The resulting expansion of the oxygen minimum zone has consequences for the region's ecosystem and biogeochemical cycles, but the causes of the oxygen decline are not yet fully understood. Here we combine models of atmospheric chemistry, ocean circulation and biogeochemical cycling to test the hypothesis that atmospheric pollution over the Pacific Ocean contributed to the redistribution of oxygen in deeper waters. We simulate the pollution-induced enhancement of atmospheric soluble iron and fixed nitrogen deposition, as well as its impacts on ocean productivity and biogeochemical cycling for the late twentieth century. The model reproduces the magnitude and large-scale pattern of the observed oxygen changes from the 1970s to the 1990s, and the sensitivity experiments reveal the reinforcing effects of pollution-enhanced iron deposition and natural climate variability. Despite the aerosol deposition being the largest in mid-latitudes, its effect on oceanic oxygen is most pronounced in the tropics, where ocean circulation transports added iron to the tropics, leading to an increased regional productivity, respiration and subsurface oxygen depletion. These results suggest that anthropogenic pollution can interact and amplify climate-driven impacts on ocean biogeochemistry, even in remote ocean biomes.

  19. Numerical analysis of the primary processes controlling oxygen dynamics on the Louisiana Shelf

    Directory of Open Access Journals (Sweden)

    L. Yu

    2014-10-01

    Full Text Available The Louisiana shelf in the northern Gulf of Mexico receives large amounts of freshwater and nutrients from the Mississippi/Atchafalaya River system. These river inputs contribute to widespread bottom-water hypoxia every summer. In this study, we use a physical-biogeochemical model that explicitly simulates oxygen sources and sinks on the Louisiana shelf to identify the key mechanisms controlling hypoxia development. First, we validate the model simulation against observed dissolved oxygen concentrations, primary production, water column respiration, and sediment oxygen consumption. In the model simulation, heterotrophy is prevalent in shelf waters throughout the year except near the mouths of the Mississippi and Atchafalaya Rivers where primary production exceeds respiratory oxygen consumption during June and July. During this time, efflux of oxygen to the atmosphere, driven by photosynthesis and surface warming, becomes a significant oxygen sink while the well-developed pycnocline isolates autotrophic surface waters from the heterotrophic and hypoxic waters below. A substantial fraction of primary production occurs below the pycnocline in summer. We investigate whether this primary production below the pycnocline is mitigating the development of hypoxic conditions with the help of a sensitivity experiment where we disable biological processes in the water column (i.e. primary production and water column respiration. In this experiment below-pycnocline primary production reduces the spatial extent of hypoxic bottom waters only slightly. Our results suggest that the combination of physical processes and sediment oxygen consumption largely determine the spatial extent and dynamics of hypoxia on the Louisiana shelf.

  20. Carbon and Oxygen Abundances in Low Metallicity Dwarf Galaxies

    Science.gov (United States)

    Berg, Danielle A.; Skillman, Evan D.; Henry, Richard B. C.; Erb, Dawn K.; Carigi, Leticia

    2016-08-01

    The study of carbon and oxygen abundances yields information on the time evolution and nucleosynthetic origins of these elements, yet they remain relatively unexplored. At low metallicities, (12+log(O/H) complemented by optical SDSS spectra, from which we measured the nebular physical conditions and oxygen abundances using the direct method. At low metallicity, (12+log(O/H) < 8.0), no clear trend is evident in C/O versus O/H for the present sample given the large dispersion observed. When combined with recombination line observations at higher values of O/H, a general trend of increasing C/O with increasing O/H is also viable but with some significant outliers. Additionally, we find the C/N ratio appears to be constant (but with significant scatter) over a large range in oxygen abundance, indicating that carbon is predominantly produced by similar nucleosynthetic mechanisms as nitrogen. If true, and our current understanding of nitrogen production is correct, this would indicate that primary production of carbon (a flat trend) dominates at low metallicity, but quasi-secondary production (an increasing trend) becomes prominent at higher metallicities. A larger sample will be needed to determine the true nature and dispersion of the relation.

  1. Catalyst morphology matters for lithium-oxygen battery cathodes

    Science.gov (United States)

    Oakes, Landon; Muralidharan, Nitin; Cohn, Adam P.; Pint, Cary L.

    2016-12-01

    The effectiveness of using catalyst nanoparticles to reduce the overpotential and energy efficiency of lithium-oxygen (or lithium-air) batteries (LOBs) is usually attributed to the inherent catalytic properties of individual nanoparticles. Here, we demonstrate that the morphology of the catalyst layer is equally important in maintaining integrity of the catalyst coating during product formation in LOBs. We demonstrate this by comparing the performance of smooth, conformal coated Mn2O3 catalyst nanoparticles prepared by electric field-assisted deposition, and more irregular coatings using conventional film assembly techniques both on three-dimensional mesh substrates. Smooth coatings lead to an improved overpotential of 50 mV during oxygen reduction and 130 mV during oxygen evolution in addition to a nearly 2X improvement in durability compared to the more irregular films. In situ electrochemical impedance spectroscopy combined with imaging studies elucidates a mechanism of morphology-directed deactivation of catalyst layers during charging and discharging that must be overcome at practical electrode scales to achieve cell-level performance targets in LOBs.

  2. Oxygen isotopic composition of low-temperature authigenic clinoptilolite

    Science.gov (United States)

    Nähr, T.; Botz, R.; Bohrmann, G.; Schmidt, M.

    1998-08-01

    Oxygen isotope ratios were obtained from authigenic clinoptilolites from Barbados Accretionary Complex, Yamato Basin, and Exmouth Plateau sediments (ODP Sites 672, 797, and 762) in order to investigate the isotopic fractionation between clinoptilolite and pore water at early diagenetic stages and low temperatures. Dehydrated clinoptilolites display isotopic ratios for the zeolite framework ( δ18O f) that extend from +18.7‰ to +32.8‰ (vs. SMOW). In combination with associated pore water isotope data, the oxygen isotopic fractionation between clinoptilolite and pore fluids could be assessed in the temperature range from 25°C to 40°C. The resulting fractionation factors of 1.032 at 25°C and 1.027 at 40°C are in good agreement with the theoretically determined oxygen isotope fractionation between clinoptilolite and water. Calculations of isotopic temperatures illustrate that clinoptilolite formation occurred at relatively low temperatures of 17°C to 29°C in Barbados Ridge sediments and at 33°C to 62°C in the Yamato Basin. These data support a low-temperature origin of clinoptilolite and contradict the assumption that elevated temperatures are the main controlling factor for authigenic clinoptilolite formation. Increasing clinoptilolite δ18O f values with depth indicate that clinoptilolites which are now in the deeper parts of the zeolite-bearing intervals had either formed at lower temperatures (17-20°C) or under closed system conditions.

  3. Dynamics of oxygen supply and consumption during mainstream large-scale composting in China.

    Science.gov (United States)

    Zeng, Jianfei; Shen, Xiuli; Han, Lujia; Huang, Guangqun

    2016-11-01

    This study characterized some physicochemical and biological parameters to systematically evaluate the dynamics of oxygen supply and consumption during large-scale trough composting in China. The results showed that long active phases, low maximum temperatures, low organic matter losses and high pore methane concentrations were observed in different composting layers. Pore oxygen concentrations in the top, middle and bottom layers maintained oxygen was consumed at a stable respiration rate to a concentration of 5vol.% in no more than 99min and remained anaerobic in the subsequent static condition. The daily percentage of time under aerobic condition was no more than 14% of a single day. Therefore, improving FAS, adjusting aeration interval or combining turning with forced aeration was suggested to provide sufficient oxygen during composting.

  4. Theoretical analysis of ozone generation by pulsed dielectric barrier discharge in oxygen

    Science.gov (United States)

    Wei, L. S.; Zhou, J. H.; Wang, Z. H.; Cen, K. F.

    2007-08-01

    The use of very short high-voltage pulses combined with a dielectric layer results in high-energy electrons that dissociate oxygen molecules into atoms, which are a prerequisite for the subsequent production of ozone by collisions with oxygen molecules and third particles. The production of ozone depends on both the electrical and the physical parameters. For ozone generation by pulsed dielectric barrier discharge in oxygen, a mathematical model, which describes the relation between ozone concentration and these parameters that are of importance in its design, is developed according to dimensional analysis theory. A formula considering the ozone destruction factor is derived for predicting the characteristics of the ozone generation, within the range of the corona inception voltage to the gap breakdown voltage. The trend showing the dependence of the concentration of ozone in oxygen on these parameters generally agrees with the experimental results, thus confirming the validity of the mathematical model.

  5. Distribution and mass transfer of dissolved oxygen in a multi-habitat membrane bioreactor.

    Science.gov (United States)

    Tang, Bing; Qiu, Bing; Huang, Shaosong; Yang, Kanghua; Bin, Liying; Fu, Fenglian; Yang, Huiwen

    2015-04-01

    This work investigated the DO distribution and the factors influencing the mass transfer of DO in a multi-habitat membrane bioreactor. Through the continuous measurements of an on-line automatic system, the timely DO values at different zones in the bioreactor were obtained, which gave a detailed description to the distribution of oxygen within the bioreactor. The results indicated that the growth of biomass had an important influence on the distribution of oxygen. As the extension of operational time, the volumetric oxygen mass transfer coefficient (kLa) was generally decreased. With the difference in DO values, a complex environment combining anoxic and oxic state was produced within a single bioreactor, which provided a fundamental guarantee for the total removal of TN. Aeration rate, the concentration and apparent viscosity of MLSS have different influences on kLa, but adjusting the viscosity is a feasible method to improve the mass transfer of oxygen in the bioreactor.

  6. Microbial respiration and gene expression as a function of very low oxygen concentration

    DEFF Research Database (Denmark)

    Tiano, Laura

    recently, due to the lack of high-resolution methods for O2 concentration determination, several oxygen-related processes, such as aerobic respiration in pelagic aquatic ecosystems and in naturally oxygen poor waters (e.g. Oxygen Minimum Zones, OMZs), or the oxygen regulation of nitrification...... on nitrite-oxidizing bacteria (NOB) and the expression of their terminal oxidases genes. The results from this project show that it is indeed possible, by combining high resolution sensor technology (the STOX sensor) and all-glass bottle incubation (Appendix A) to achieve an extreme high sensitivity in O2...... detection (1-10 nM, and ~ 2 nM O2 /h, for respiration rates) (Manuscript I, II and IV). Thus this new method allows for precise determination of respiration rates also in low activity waters, within few hours of incubation time (Manuscript II). This low-O2 STOX based method has been compared with other...

  7. The role of oxygen and water on molybdenum nanoclusters for electro catalytic ammonia production

    DEFF Research Database (Denmark)

    Howalt, Jakob Geelmuyden; Vegge, Tejs

    2014-01-01

    . In this study, we present theoretical investigations of the influence of oxygen adsorption and reduction on pure and nitrogen covered molybdenum nanocluster electro catalysts for electrochemical reduction of N2 to NH3 with the purpose of understanding oxygen and water poisoning of the catalyst. Density...... functional theory calculations are used in combination with the computational hydrogen electrode approach to calculate the free energy profile for electrochemical protonation of O and N2 species on cuboctahedral Mo13 nanoclusters. The calculations show that the molybdenum nanocluster will preferentially bind...... are -0.72 V or lower for all oxygen coverages studied, and it is thus possible to (re)activate (partially) oxidized nanoclusters for electrochemical ammonia production, e.g., using a dry proton conductor or an aqueous electrolyte. At lower oxygen coverages, nitrogen molecules can adsorb to the surface...

  8. Clinical value and influencing factors of intraoperative monitoring of jugular venous oxygen saturation

    Directory of Open Access Journals (Sweden)

    Jie SONG

    2016-10-01

    Full Text Available Intraoperative jugular venous oxygen saturation (SjvO2 monitoring has been widely used in clinic, which can monitor cerebral blood flow (CBF and oxygen metabolism. Reverse puncture and catheterization through jugular vein for monitoring SjvO2 is easy to operate and can collect blood samples repeatedly. It is an effective method for real-time dynamic evaluation of cerebral oxygen supply-demand and neurological function. This article reviews the clinical significance and influencing factors of SjvO2 monitoring during operation. It notes in particular that SjvO2 can not be used as the only way to monitor CBF and oxygen metabolism, and a comprehensive evaluation should be done combining with the change of other parameters. DOI: 10.3969/j.issn.1672-6731.2016.10.014

  9. Oxygen and animal evolution: Did a rise of atmospheric oxygen trigger the origin of animals?

    DEFF Research Database (Denmark)

    Mills, Daniel Brady; Canfield, Donald Eugene

    2014-01-01

    Recent studies challenge the classical view that the origin of animal life was primarily controlled by atmospheric oxygen levels. For example, some modern sponges, representing early-branching animals, can live under 200 times less oxygen than currently present in the atmosphere - levels commonly...... thought to have been maintained prior to their origination. Furthermore, it is increasingly argued that the earliest animals, which likely lived in low oxygen environments, played an active role in constructing the well-oxygenated conditions typical of the modern oceans. Therefore, while oxygen is still...

  10. Carbon mineralization and oxygen dynamics in sediments with deep oxygen penetration, Lake Superior

    DEFF Research Database (Denmark)

    Li, Jiying; Crowe, Sean Andrew; Miklesh, David;

    2012-01-01

    penetration is explained by low sedimentation rates (0.01–0.04 cm yr−1), high solubility of oxygen in freshwater, and a shallow (∼ 2 cm) bioturbation zone. In response mainly to oxygen variations in the bottom waters, the sediment oxygen penetration varied seasonally by as much as several centimeters......, suggesting that temporal variability in deeply oxygenated sediments may be greater than previously acknowledged. The oxygen uptake rates (4.4–7.7 mmol m−2 d−1, average 6.1 mmol m−2 d−1) and carbon mineralization efficiency (∼ 90% of deposited carbon) were similar to those in marine hemipelagic and pelagic...

  11. Modifications of Oxygen Saturation During Transesophageal Echocardiography.

    Science.gov (United States)

    Macor, Franco; Zottarel, Gabriella; Antonini-Canterin, Francesco; Mimo, Renata; Pavan, Daniela; Cervesato, Eugenio; Nicolosi, Gianluigi; Zanuttini, Domenico

    1997-05-01

    The present study was designed: (1) to establish the effects of transesophageal echocardiography (TEE) on arterial oxygen saturation (SAO(2)%); (2) to verify the possible clinical consequences of this phenomenon; and (3) to study the possibility of predicting modifications of SAO(2)% by clinical or hemodynamic variables or by specific factors related to the TEE procedure. We prospectively studied 116 unselected patients, aged 61 +/- 12 years, who underwent diagnostic TEE for various clinical indications. Thirty-seven patients had mitral valve disease, 19 aortic valve disease, 14 combined mitroaortic disease, 8 congenital heart disease, and 38 other cardiovascular diseases. Eight patients were affected by chronic obstructive pulmonary disease. Ninety-seven patients were sedated by 4 +/- 2 mg of diazepam IV SAO(2)% (5-min average) (Ohmeda Biox 3700 pulse oxymeter finger probe), heart rate (HR), and blood pressure (BP) were considered during baseline transthoracic examination, after pharmacological sedation but before the introduction of the probe, and finally during TEE. Neither clinical complications nor major arrhythmias were observed. Baseline SAO(2)%, HR and BP were, respectively, 93.6 +/- 3.3%, 76 +/- 14 beats/min, and 129 +/- 20/75 +/- 10 mmHg. Pharmacological sedation did not modify SAO(2)%, HR, and BP (P > 0.1). During TEE a small but significant reduction in SAO(2)% by an average of 1.2 +/- 3.2% was observed (P 0.1 for both systolic and diastolic). The changes of SAO(2)% and HR were not interrelated and were not related to the duration of the procedure and to any of the clinical and hemodynamic variables taken into consideration. TEE can induce a small but significant drop in SAO(2)% and a small increase in HR even without any clinical relevance. No clinical or hemodynamic variable or specific factors related to the TEE procedure were related to these changes.

  12. Heme biomolecule as redox mediator and oxygen shuttle for efficient charging of lithium-oxygen batteries

    Science.gov (United States)

    Ryu, Won-Hee; Gittleson, Forrest S.; Thomsen, Julianne M.; Li, Jinyang; Schwab, Mark J.; Brudvig, Gary W.; Taylor, André D.

    2016-10-01

    One of the greatest challenges with lithium-oxygen batteries involves identifying catalysts that facilitate the growth and evolution of cathode species on an oxygen electrode. Heterogeneous solid catalysts cannot adequately address the problematic overpotentials when the surfaces become passivated. However, there exists a class of biomolecules which have been designed by nature to guide complex solution-based oxygen chemistries. Here, we show that the heme molecule, a common porphyrin cofactor in blood, can function as a soluble redox catalyst and oxygen shuttle for efficient oxygen evolution in non-aqueous Li-O2 batteries. The heme's oxygen binding capability facilitates battery recharge by accepting and releasing dissociated oxygen species while benefiting charge transfer with the cathode. We reveal the chemical change of heme redox molecules where synergy exists with the electrolyte species. This study brings focus to the rational design of solution-based catalysts and suggests a sustainable cross-link between biomolecules and advanced energy storage.

  13. Space Station evolution study oxygen loop closure

    Science.gov (United States)

    Wood, M. G.; Delong, D.

    1993-01-01

    In the current Space Station Freedom (SSF) Permanently Manned Configuration (PMC), physical scars for closing the oxygen loop by the addition of oxygen generation and carbon dioxide reduction hardware are not included. During station restructuring, the capability for oxygen loop closure was deferred to the B-modules. As such, the ability to close the oxygen loop in the U.S. Laboratory module (LAB A) and the Habitation A module (HAB A) is contingent on the presence of the B modules. To base oxygen loop closure of SSF on the funding of the B-modules may not be desirable. Therefore, this study was requested to evaluate the necessary hooks and scars in the A-modules to facilitate closure of the oxygen loop at or subsequent to PMC. The study defines the scars for oxygen loop closure with impacts to cost, weight and volume and assesses the effects of byproduct venting. In addition, the recommended scenarios for closure with regard to topology and packaging are presented.

  14. Boron PLA for oxygen sensing & hypoxia imaging

    Directory of Open Access Journals (Sweden)

    Cassandra L. Fraser

    2009-10-01

    Full Text Available Oxygen is essential for many forms of life and its depletion in the body and the environment can lead to deleterious effects. Low oxygen conditions, even anoxia, are associated with eutrophication of lakes and rivers, wherein an over abundance of nutrients often caused by pollution result in excessive plant growth and decay, threatening water quality, ecosystem balance, and aquatic life. In the body, low oxygen conditions or hypoxia may be generalized, as can occur at high altitude or during strenuous exercise, or localized in particular tissues, when there is a mismatch between oxygen supply and demand. Hypoxia is present in many important diseases as well. Low oxygen levels in tumors are often associated with biochemical changes, increased invasiveness, cancer progression, and resistance to radiation and chemotherapies. Vascular blockage in strokes, heart attacks, and peripheral artery disease, which is common in diabetes, are other situations where oxygen levels can drop precipitously and cause great damage to affected tissues. Clearly, innovative sensing technologies that provide new insight into these many oxygen dependent processes can impact global society in significant ways.

  15. Low Oxygen Response Mechanisms in Green Organisms

    Directory of Open Access Journals (Sweden)

    Pierdomenico Perata

    2013-02-01

    Full Text Available Low oxygen stress often occurs during the life of green organisms, mostly due to the environmental conditions affecting oxygen availability. Both plants and algae respond to low oxygen by resetting their metabolism. The shift from mitochondrial respiration to fermentation is the hallmark of anaerobic metabolism in most organisms. This involves a modified carbohydrate metabolism coupled with glycolysis and fermentation. For a coordinated response to low oxygen, plants exploit various molecular mechanisms to sense when oxygen is either absent or in limited amounts. In Arabidopsis thaliana, a direct oxygen sensing system has recently been discovered, where a conserved N-terminal motif on some ethylene responsive factors (ERFs, targets the fate of the protein under normoxia/hypoxia. In Oryza sativa, this same group of ERFs drives physiological and anatomical modifications that vary in relation to the genotype studied. The microalga Chlamydomonas reinhardtii responses to low oxygen seem to have evolved independently of higher plants, posing questions on how the fermentative metabolism is modulated. In this review, we summarize the most recent findings related to these topics, highlighting promising developments for the future.

  16. Oxygen radicals, inflammation, and tissue injury.

    Science.gov (United States)

    Ward, P A; Warren, J S; Johnson, K J

    1988-01-01

    Inflammatory reactions often result in the activation and recruitment of phagocytic cells (e.g., neutrophils and/or tissue macrophages) whose products result in injury to the tissue. In killing of endothelial cells by activated neutrophils as well as in lung injury produced by either activated neutrophils or activated macrophages there is evidence that H2O2 and iron play a role. HO. may be a key oxygen product related to the process of injury. Endothelial cells in some vascular compartments may be susceptible to neutrophil mediated injury in a manner that is independent of oxygen radicals. On the basis of in vitro observations, a synergy exits between platelets and neutrophils, resulting in enhanced oxygen radical formation by the latter. Finally, the cytokines, interleukin 1 and tumor necrosis factor, released from macrophages have both direct stimulatory effects on oxygen radical formation in neutrophils and can "prime" macrophages for enhanced oxygen radical responses to other agonists. Cytokines may also alter endothelial cells rendering them more susceptible to oxygen radical mediated injury by neutrophils. This suggests a complex network of interactions between phagocytic cells and peptide mediators, the result of which is acute, oxygen radical mediated tissue injury.

  17. Oxygen Requirements for the Cambrian Explosion

    Institute of Scientific and Technical Information of China (English)

    Xingliang Zhang; Linhao Cui

    2016-01-01

    Hypoxic tolerance experiments may be helpful to constrain the oxygen requirement for animal evolution. Based on literature review, available data demonstrate that fishes are more sensitive to hypoxia than crustaceans and echinoderms, which in turn are more sensitive than annelids, whilst mollusks are the least sensitive. Mortalities occur where O2 concentrations are below 2.0 mg/L, equivalent to saturation with oxygen content about 25% PAL (present atmospheric level). Therefore, the minimal oxygen requirement for maintaining animal diversity since Cambrian is determined as 25% PAL. The traditional view is that a rise in atmospheric oxygen concentrations led to the oxygenation of the ocean, thus triggering the evolution of animals. Geological and geochemical studies suggest a constant increase of the oxygen level and a contraction of anoxic oceans during Ediacaran–Cambrian transition when the world oceans experienced a rapid diversification of metazoan lineages. However, fossil first appearances of animal phyla are obviously asynchronous and episodic, showing a sequence as:basal metazoans>lophotrochozoans>ecdysozoans and deuterostomes. According to hitherto known data of fossil record and hypoxic sensitivity of animals, the appearance sequence of different animals is broadly consistent with their hypoxic sensitivity:animals like molluscs and annelids that are less sensitive to hypoxia appeared earlier, while animals like echinoderms and fishes that are more sensitive to hypoxia came later. Therefore, it is very likely that the appearance order of animals is corresponding to the increasing oxygen level and/or the contraction of anoxic oceans during Ediacaran–Cambrian transition.

  18. Compact intra- and extracorporeal oxygenator developments.

    Science.gov (United States)

    Cattaneo, Giorgio; Strauss, Andreas; Reul, Helmut

    2004-07-01

    For patients with acute lung failure, mechanical ventilation entails the risk of lung tissue damage due to high oxygen pressure and concentration. Membrane oxygenation for one to two weeks can rest the lungs due to decreased ventilation parameters, representing a potential bridge to recovery, but implies the substantial risks of blood damage, plasma leakage and infection, which often have fatal results for patients. At the Helmholtz Institute in Aachen, two types of membrane oxygenators, which aim to overcome previous limits, are under development. Both present compact designs, reduced surface and priming volumes and easier handling. HEXMO is a miniaturized extracorporeal membrane oxygenator. The integration of a small rotary blood pump into the centre of the oxygenator reduces the amount of tubing and connectors in the system. Blood is convectively warmed by the pump motor housing, thus, the use of a heat-exchanger can be avoided. This compact design reduces surface and priming volume and allows better handling, especially in critical situations. A second development is the intravascular oxygenator HIMOX, which is inserted directly into the vena cava. Priming volume and blood contact surface are reduced, as well as infection risk and control needs for the patient. A new cross-flow fibre configuration is used for improving gas transfer within the limited space inside the vena cava. A microaxial blood pump is integrated into the device for compensating the pressure drop across the fibres and allowing venous return and physiological pressure in the organs proximal to the oxygenator.

  19. Oxygen tension level and human viral infections

    Energy Technology Data Exchange (ETDEWEB)

    Morinet, Frédéric, E-mail: frederic.morinet@sls.aphp.fr [Centre des Innovations Thérapeutiques en Oncologie et Hématologie (CITOH), CHU Saint-Louis, Paris (France); Université Denis Diderot, Sorbonne Paris Cité Paris, Paris (France); Casetti, Luana [Institut Cochin INSERM U1016, Paris (France); François, Jean-Hugues; Capron, Claude [Institut Cochin INSERM U1016, Paris (France); Laboratoire d' Hématologie, Hôpital Ambroise Paré, Boulogne (France); Université de Versailles Saint-Quentin en Yvelynes, Versailles (France); Pillet, Sylvie [Laboratoire de Bactériologie-Virologie-Hygiène, CHU de Saint-Etienne, Saint-Etienne (France); Université de Lyon et Université de Saint-Etienne, Jean Monnet, GIMAP EA3064, F-42023 Saint-Etienne, Lyon (France)

    2013-09-15

    The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition. - Highlights: • Oxygen tension level regulates viral replication in vitro and possibly in vivo. • Hypoxia-inducible factor 1 (HIF-1α) is the principal factor involved in Oxygen tension level. • HIF-1α upregulates gene expression for example of HIV, JC and Kaposi sarcoma viruses. • In addition to classical chemotherapy inhibition of HIF-1α may constitute a new track to treat human viral infections.

  20. Astrocytic mitochondrial membrane hyperpolarization following extended oxygen and glucose deprivation.

    Science.gov (United States)

    Korenić, Andrej; Boltze, Johannes; Deten, Alexander; Peters, Myriam; Andjus, Pavle; Radenović, Lidija

    2014-01-01

    Astrocytes can tolerate longer periods of oxygen and glucose deprivation (OGD) as compared to neurons. The reasons for this reduced vulnerability are not well understood. Particularly, changes in mitochondrial membrane potential (Δψ(m)) in astrocytes, an indicator of the cellular redox state, have not been investigated during reperfusion after extended OGD exposure. Here, we subjected primary mouse astrocytes to glucose deprivation (GD), OGD and combinations of both conditions varying in duration and sequence. Changes in Δψ(m), visualized by change in the fluorescence of JC-1, were investigated within one hour after reconstitution of oxygen and glucose supply, intended to model in vivo reperfusion. In all experiments, astrocytes showed resilience to extended periods of OGD, which had little effect on Δψ(m) during reperfusion, whereas GD caused a robust Δψ(m) negativation. In case no Δψ(m) negativation was observed after OGD, subsequent chemical oxygen deprivation (OD) induced by sodium azide caused depolarization, which, however, was significantly delayed as compared to normoxic group. When GD preceded OD for 12 h, Δψ(m) hyperpolarization was induced by both GD and subsequent OD, but significant interaction between these conditions was not detected. However, when GD was extended to 48 h preceding OGD, hyperpolarization enhanced during reperfusion. This implicates synergistic effects of both conditions in that sequence. These findings provide novel information regarding the role of the two main substrates of electron transport chain (glucose and oxygen) and their hyperpolarizing effect on Δψ(m) during substrate deprivation, thus shedding new light on mechanisms of astrocyte resilience to prolonged ischemic injury.

  1. Astrocytic mitochondrial membrane hyperpolarization following extended oxygen and glucose deprivation.

    Directory of Open Access Journals (Sweden)

    Andrej Korenić

    Full Text Available Astrocytes can tolerate longer periods of oxygen and glucose deprivation (OGD as compared to neurons. The reasons for this reduced vulnerability are not well understood. Particularly, changes in mitochondrial membrane potential (Δψ(m in astrocytes, an indicator of the cellular redox state, have not been investigated during reperfusion after extended OGD exposure. Here, we subjected primary mouse astrocytes to glucose deprivation (GD, OGD and combinations of both conditions varying in duration and sequence. Changes in Δψ(m, visualized by change in the fluorescence of JC-1, were investigated within one hour after reconstitution of oxygen and glucose supply, intended to model in vivo reperfusion. In all experiments, astrocytes showed resilience to extended periods of OGD, which had little effect on Δψ(m during reperfusion, whereas GD caused a robust Δψ(m negativation. In case no Δψ(m negativation was observed after OGD, subsequent chemical oxygen deprivation (OD induced by sodium azide caused depolarization, which, however, was significantly delayed as compared to normoxic group. When GD preceded OD for 12 h, Δψ(m hyperpolarization was induced by both GD and subsequent OD, but significant interaction between these conditions was not detected. However, when GD was extended to 48 h preceding OGD, hyperpolarization enhanced during reperfusion. This implicates synergistic effects of both conditions in that sequence. These findings provide novel information regarding the role of the two main substrates of electron transport chain (glucose and oxygen and their hyperpolarizing effect on Δψ(m during substrate deprivation, thus shedding new light on mechanisms of astrocyte resilience to prolonged ischemic injury.

  2. Treatment of femoral head osteonecrosis with core decompression and subsequent hyperbaric oxygen therapy

    Directory of Open Access Journals (Sweden)

    Alper Deveci

    2013-06-01

    Full Text Available Aim. Regardless the etiologic factor, femoral head avascular necrosis is a process that occurs with femoral head local blood supply deficiency. The purpose of our study was to evaluate the clinical and radiologic outcomes in patients diagnozed with grade 1 and 2 avascular necrosis of the femoral head who were treated with a combination of core decompression and hyperbaric oxygen therapy. Method. In our study we have evaluated 21 hips of 16 patients retrospectively, which we have treated with a combination of core decompression and hyperbaric oxygen therapy. We performed clinical and radiological evaluation to the patients. Result. VAS and Harris hip scores showed improvement in all of our patients except in short term results. Conclusion. Core decompression and subsequent hyperbaric oxygen therapy are accomplishing each other because of their synergistic effects.

  3. Coping with cyclic oxygen availability: evolutionary aspects.

    Science.gov (United States)

    Flück, Martin; Webster, Keith A; Graham, Jeffrey; Giomi, Folco; Gerlach, Frank; Schmitz, Anke

    2007-10-01

    Both the gradual rise in atmospheric oxygen over the Proterozoic Eon as well as episodic fluctuations in oxygen over several million-year time spans during the Phanerozoic Era, have arguably exerted strong selective forces on cellular and organismic respiratory specialization and evolution. The rise in atmospheric oxygen, some 2 billion years after the origin of life, dramatically altered cell biology and set the stage for the appearance of multicelluar life forms in the Vendian (Ediacaran) Period of the Neoproterozoic Era. Over much of the Paleozoic, the level of oxygen in the atmosphere was near the present atmospheric level (21%). In the Late Paleozoic, however, there were extended times during which the level of atmospheric oxygen was either markedly lower or markedly higher than 21%. That these Paleozoic shifts in atmospheric oxygen affected the biota is suggested by the correlations between: (1) Reduced oxygen and the occurrences of extinctions, a lowered biodiversity and shifts in phyletic succession, and (2) During hyperoxia, the corresponding occurrence of phenomena such as arthropod gigantism, the origin of insect flight, and the evolution of vertebrate terrestriality. Basic similarities in features of adaptation to hyopoxia, manifest in living organisms at levels ranging from genetic and cellular to physiological and behavioral, suggest the common and early origin of a suite of adaptive mechanisms responsive to fluctuations in ambient oxygen. Comparative integrative approaches addressing the molecular bases of phenotypic adjustments to cyclic oxygen fluctuation provide broad insight into the incremental steps leading to the early evolution of homeostatic respiratory mechanisms and to the specialization of organismic respiratory function.

  4. Oxygen - A Four Billion Year History

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene

    guides readers through the various lines of scientific evidence, considers some of the wrong turns and dead ends along the way, and highlights the scientists and researchers who have made key discoveries in the field. Showing how Earth's atmosphere developed over time, Oxygen takes readers...... of fields, including geology, paleontology, geochemistry, biochemistry, animal physiology, and microbiology, to explain why our oxygenated Earth became the ideal place for life. Describing which processes, both biological and geological, act to control oxygen levels in the atmosphere, Canfield traces...

  5. Recovery function of light quantum autohemo-oxygen therapy combined with decoction of activating blood circulation on stroke patients%光量子自血氧疗合通窍活血汤对脑卒中的康复作用

    Institute of Scientific and Technical Information of China (English)

    张银清; 刘卫平

    2001-01-01

    @@Background:Drug therapy of hypertension is common in clinic.But hypertension will reocur when drug treatment is arrested.Hypertension belongs to headache and dizziness in chinese medicine.The liver-gas,stagnated fire,fire-transmission,deficiency of the kidney-yin,hyperactivity of the liver-yang may contributed to its development. Objective:To treat hypertension with exercise combined with drugs. Design:173 patients with hypertension were randomly divided into two groups,treatment group and control group.Patients in treatment group recepted exercise therapy,for patients with severe hypertension,Xaiozhiyin was administered.Patients in control group recepted oral Xiaozhiyin. Unit:Hangzhou Tianmushan Pharmacy Company,Hangzhou Subjects:173 hypertension patients,79 male,94 female,aged from 35~ 70 years.Disease variated between 1~ 32 years.Grade of hypertension is I in 36 cases,II in 69 patients,III in 48 patients and IV in 20 patients.All patients underwent different levels of headache,dissziness,insomnia and fatigue.They were randomly divided into treatment group and control group.There were no significant differences in age,sex,blood pressure,signs and symptoms between two groups.Intervention:(1)Patients in treatment group carried out exercise such as swimming,dancing,jogging and shadow boxing.Exercise intensity was determined according to patients'endurance and time.Exercise duration lasted for 30~ 60 min.For patients with severe hypertension in treatment group,Xaiozhiyin consisted of 15 mg cassia seed,10 mg Hawthorn fruit,Long fleece-flower root,10 mg Bighead atractylodes rhizome,1 dosage/day,total 8 weeks was administered.(2)patients in control group received oral Xiaozhiyin.

  6. Vasopressin and angiotensin II stimulate oxygen uptake in the perfused rat hindlimb

    DEFF Research Database (Denmark)

    Colquhoun, E Q; Hettiarachchi, M; Ye, J M;

    1988-01-01

    uptake and pressure were not inhibited by either phentolamine, propranolol or a combination of the two, but were completely inhibited by the vasodilator, nitroprusside. Nitroprusside also inhibited flow-induced increases in hindlimb oxygen uptake and perfusion pressure. The findings indicate a key role...

  7. Hydroxylamine as an oxygen nucleophile: substitution of sulfonamide by a hydroxyl group in benzothiazole-2-sulfonamides

    NARCIS (Netherlands)

    Kamps, J.; Belle, R.; Mecinovic, J.

    2013-01-01

    Benzothiazole-2-sulfonamides react with an excess of hydroxylamine in aqueous solutions to form 2-hydroxybenzothiazole, sulfur dioxide, and the corresponding amine. Mechanistic studies that employ a combination of structure-reactivity relationships, oxygen labeling experiments, and (in)direct detect

  8. Operational Considerations for Oxygen Flammability Risks: Concentrated Oxygen Diffusion and Permeation Behaviors

    Science.gov (United States)

    Harper, Susana; Smith, Sarah; Juarez, Alfredo; Hirsch, David

    2010-01-01

    Increased human spaceflight operations utilize oxygen concentrations that are frequently varied with use of concentrations up to 100 percent oxygen. Even after exiting a higher percentage oxygen environment, high oxygen concentrations can still be maintained due to material saturation and oxygen entrapment between barrier materials. This paper examines the material flammability concerns that arise from changing oxygen environments during spaceflight operations. We examine the time required for common spacecraft and spacesuit materials exposed to oxygen to return to reduced ignitability and flammability once removed from the increased concentration. Various common spacecraft materials were considered: spacecraft cabin environment foams, Extra Vehicular Mobility Unit materials and foams, Advanced Crew Escape Suit materials, and other materials of interest such as Cotton, Nomex^ HT90-40, and Tiburon Surgical Drape. This paper presents calculated diffusion coefficients derived from experimentally obtained oxygen transmission rates for the tested materials and the analytically derived times necessary for reduced flammability to be achieved based on NASA flammability criteria. Oxygen material saturation and entrapment scenarios are examined. Experimental verification data on oxygen diffusion in saturation scenarios are also presented and discussed. We examine how to use obtained data to address flammability concerns during operational planning to reduce the likelihood of fires while improving efficiency for procedures.

  9. Oxygen therapy multicentric study--a nationwide audit to oxygen therapy procedures in internal medicine wards.

    Science.gov (United States)

    Neves, J T; Lobão, M J

    2012-01-01

    Oxygen therapy is a common and important treatment in Internal Medicine wards, however, several studies report that it isn't provided accordingly with the best of care. The goal of this work is to evaluate oxygen therapy procedures in Portuguese Internal Medicine wards, comparing them to the standards established by the British Thoracic Society (BTS) in its consensus statement "BTS guideline for emergency oxygen use in adult patients". Between September 3rd and 23rd 2010, each one of the 24 enrolled hospitals audited the oxygen therapy procedures for one randomly chosen day. All Internal Medicine inpatients under oxygen therapy or with oxygen prescription were included. Data was collected regarding oxygen prescription, administration and monitoring. Of the 1549 inpatients, 773 met inclusion criteria. There was an oxygen prescription in 93,4%. Most prescriptions were by a fixed dose (82,4%), but only 11,6% of those stated all the required parameters. Absence of oxygen therapy duration and monitoring were the most frequent errors. Oxygen was administered to only 77,0% of the patients with fixed dose prescriptions. FiO(2) or flow rate and the delivery device were the same as prescribed in 70,9 and 89,2% of the patients, respectively. Out of the 127 patients with oxygen therapy prescriptions by target SatO(2) range, 82,7% were on the prescribed SatO(2) objective range. Several errors were found in oxygen therapy procedures, particularly regarding fixed dose prescriptions, jeopardizing the patients. Although recommended by BTS, oxygen therapy prescriptions by target SatO(2) range are still a minority.

  10. The impact of arterial oxygen tension on venous oxygen saturation in circulatory failure.

    Science.gov (United States)

    Ho, Kwok Ming; Harding, Richard; Chamberlain, Jenny

    2008-01-01

    Central and mixed venous oxygen saturations have been used to guide resuscitation in circulatory failure, but the impact of arterial oxygen tension on venous oxygen saturation has not been thoroughly evaluated. This observational study investigated the impact of arterial oxygen tension on venous oxygen saturation in circulatory failure. Twenty critically ill patients with circulatory failure requiring mechanical ventilation and a pulmonary artery catheter in an intensive care unit in a tertiary hospital in Western Australia were recruited. Samples of arterial blood, central venous blood, and mixed venous blood were simultaneously and slowly drawn from the arterial, central venous, and pulmonary artery catheter, respectively, at baseline and after the patient was ventilated with 100% inspired oxygen for 5 min. The blood samples were redrawn after a significant change in cardiac index (>or =10%) from the baseline, occurring within 24 h of study enrollment while the patient was ventilated with the same baseline inspired oxygen concentration, was detected. An increase in inspired oxygen concentration significantly increased the arterial oxygen tension from 12.5 to 38.4 kPa (93.8-288 mmHg) (mean difference, 25.9 kPa; 95% confidence interval [CI], 7.5-31.9 kPa; P arterial oxygen tension on venous oxygen saturation was more significant than the effect associated with changes in cardiac index (mean difference, 2.8%; 95% CI, -0.2% to 5.8%; P = 0.063). In conclusion, arterial oxygen tension has a significant effect on venous oxygen saturation, and this effect is more significant and consistent than the effect associated with changes in cardiac index.

  11. A Compact Medical Oxygen Generator for Spacecraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An on-board oxygen concentrator is required during long duration manned space missions to supply medical oxygen. Commercial medical oxygen generators are pressure...

  12. A Low-Power Medical Oxygen Generator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An on-board oxygen concentrator is required during long duration manned space missions to supply medical oxygen. The commercial medical oxygen generators based on...

  13. Next Generation Life Support (NGLS): Variable Oxygen Regulator (VOR) Element

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the Variable Oxygen Regulator Element is to develop an oxygen-rated, contaminant-tolerant oxygen regulator to control suit pressure with a...

  14. A Solar Powered, Ceramic Oxygen Concentrator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Oxygen is an essential treatment for several life-threatening conditions including pneumonia, the single biggest cause of death in children less than five years of...

  15. A white dwarf with an oxygen atmosphere

    Science.gov (United States)

    Kepler, S. O.; Koester, Detlev; Ourique, Gustavo

    2016-04-01

    Stars born with masses below around 10 solar masses end their lives as white dwarf stars. Their atmospheres are dominated by the lightest elements because gravitational diffusion brings the lightest element to the surface. We report the discovery of a white dwarf with an atmosphere completely dominated by oxygen, SDSS J124043.01+671034.68. After oxygen, the next most abundant elements in its atmosphere are neon and magnesium, but these are lower by a factor of ≥25 by number. The fact that no hydrogen or helium are observed is surprising. Oxygen, neon, and magnesium are the products of carbon burning, which occurs in stars at the high-mass end of pre-white dwarf formation. This star, a possible oxygen-neon white dwarf, will provide a rare observational test of the evolutionary paths toward white dwarfs.

  16. Energy management study for lunar oxygen production

    Science.gov (United States)

    Fazzolare, R. A.; Wong-Swanson, B. G.

    1989-01-01

    Energy management opportunities in the process of hydrogen reduction of ilmenite for lunar oxygen production are being investigated. An optimal energy system to supply the power requirements for the process will be determined.

  17. Oxygen minimum seafloor ecological (mal) functioning

    Digital Repository Service at National Institute of Oceanography (India)

    Moodley, L.; Nigam, R.; Ingole, B.S.; PrakashBabu, C.; Panchang, R.; Nanajkar, M.; Sivadas, S.; van Breugel, P.; van Ijzerloo, L.; Rutgers, R.; Heip, C.H.R.; Soetaert, K.; Middelburg, J.J.

    under certain oceanic settings such as the oxygen minimum zones (OMZ) where OM accumulates in underlying sediments. A basic question that remains is as to what extent this Corg accumulation reflects ecological ‘malfunctioning’ or a shunting of ecological...

  18. Transcutaneous Determination of Arterial Oxygen Tension

    Science.gov (United States)

    Fenner, A.; And Others

    1975-01-01

    Evaluated were two techniques (the conventional method and the new transcutaneous method) of measuring arterial oxygen tension in 20 severely ill preterm and term infants and in 70 healthy infants. (Author/CL)

  19. Hyperbaric oxygen treatment for haemorrhagic radiation cystitis

    Energy Technology Data Exchange (ETDEWEB)

    Bevers, R.F.M.; Kurth, K.H. [Amsterdam Univ. (Netherlands). Academic Medical Center; Bakker, D.J. [Amsterdam Univ. (Netherlands). Depts. of Urology and Surgery

    1995-09-23

    Radiation-induced severe haemorrhagic cystitis is difficult to treat. Conventional treatments may decrease haematuria but do not affect the radiocystitis itself. Hyperbaric oxygen treatment has been reported to do both. We report the results of a prospective study of hyperbaric oxygen (20 sessions of 100% oxygen inhalation at 3 bar for 90 min in a multiplace hyperbaric chamber) to 40 patients with biopsy-proven radiation cystitis and severe haematuria. Haematuria disappeared completely or improved in 37 patients after treatment. Mean follow-up was 23.1 months (range 1-74); and the recurrence rate was 0.12/year. There were no adverse effects. Hyperbaric oxygen treatment should be considered for patients with severe radiation-induced haematuria. (author).

  20. Regulation of atmospheric oxygen during the Proterozoic

    Science.gov (United States)

    Laakso, Thomas A.; Schrag, Daniel P.

    2014-02-01

    Many studies suggest that oxygen has remained near modern levels throughout the Phanerozoic, but was much less abundant from the “Great Oxygenation Event” around 2.4 Ga until the late Neoproterozoic around 600 Ma (Kump, 2008). Using a simple model, we show that the maintenance of atmospheric pO2 at ∼1% of present atmospheric levels (PAL) is inconsistent with modern biogeochemical cycling of carbon, sulfur and iron unless new feedbacks are included. Low oxygen conditions are stable in our model if the flux of phosphorus to the oceans was greatly reduced during the Proterozoic. We propose a mechanism to reduce this flux through the scavenging of phosphate ions with an “iron trap” driven by greater surface mobility of ferrous iron in a low pO2 world. Incorporating this feedback leads to two stable equilibria for atmospheric oxygen, the first quantitative hypothesis to explain both Proterozoic and Phanerozoic O2 concentrations.

  1. Semiconductors and semimetals oxygen in silicon

    CERN Document Server

    Willardson, Robert K; Beer, Albert C; Shimura, Fumio

    1994-01-01

    This volume reviews the latest understanding of the behavior and roles of oxygen in silicon, which will carry the field into the ULSI era from the experimental and theoretical points of view. The fourteen chapters, written by recognized authorities representing industrial and academic institutions, cover thoroughly the oxygen related phenomena from the crystal growth to device fabrication processes, as well as indispensable diagnostic techniques for oxygen.Key Features* Comprehensive study of the behavior of oxygen in silicon* Discusses silicon crystals for VLSI and ULSI applications* Thorough coverage from crystal growth to device fabrication* Edited by technical experts in the field* Written by recognized authorities from industrial and academic institutions* Useful to graduate students, scientists in other disciplines, and active participants in the arena of silicon-based microelectronics research* 297 original line drawings

  2. Hyperbaric oxygen therapy reduces renal lactate production

    DEFF Research Database (Denmark)

    Nørlinger, Thomas S; Nielsen, Per Mose; Qi, Haiyun

    2017-01-01

    Intrarenal hypoxia is an acknowledged factor contributing to the development of diabetic nephropathy. Hyperbaric oxygen (HBO) therapy is a well-known adjuvant treatment for several medical conditions, such as decompression sickness, infections, and wound healing. The underlying metabolic response...

  3. OPTIMUM DESIGN OF LIQUID OXYGEN CONTAINERS.

    Science.gov (United States)

    work conducted in areas where information was lacking. Description of the design and construction of a liquid oxygen container together with the thermal test results on the container is included. (Author)

  4. Bartolome Island, Galapagos Stable Oxygen Calibration Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Galapagos Coral Stable Oxygen Calibration Data. Sites: Bartolome Island: 0 deg, 17'S, 90 deg 33' W. Champion Island: 1 deg, 15'S, 90 deg, 05' W. Urvina Bay (Isabela...

  5. Oxygen Candle Background for Subs and Space

    Science.gov (United States)

    Graf, John

    2017-01-01

    "At any time and without warning, a submarine may have to remain submerged for several days on account of the presence of the enemy, or rough weather, or serious accident to the machinery. Fortunately such occurrences are rare; but every commanding officer must be prepared to meet such an emergency that will afford his men the greatest possible chance of survival." Reference (1) This quotation is taken from a review of submarine air purification technology published by the Bureau of Medicine and Surgery in 1919. At that time, the U.S. Navy had just begun to experiment with possible air purification devices and supplies of oxygen that might permit submarines to remain submerged longer that the untreated closed atmosphere would allow. Submariners were exposed to elevated levels of carbon dioxide and reduced levels of oxygen that would be considered completely unacceptable by current standards. It was a different world, but humans are still humans, and the requirements for safe and effective functioning in a self-contained environment are really unchanged. The maximum submergence time for submarines as published in that work was approximately 48 hours, reference (1) In early submarines, the preferred supply of oxygen was 1800 psig compressed gas bled into the boat as needed, references (1,2). The need for added oxygen was occasionally "measured" by the physiological impact on the crew rather than a reliable instrument, reference (1). The design of submarine oxygen supply was limited to approximately 25 day submerged operation, reference (2). It was not until 1958 that U.S. submarines were able to carry out dives beyond that period and necessitated new sources of oxygen, reference (2). A curious second source of oxygen at the time was compressed air vessels that were bled into the boat while "vitiated" air (air with reduced oxygen and elevated carbon dioxide) from the opposite end of the boat was compressed into waiting empty vessels, reference (1). The periodic use of

  6. Severe Combined Immunodeficiency (SCID)

    Science.gov (United States)

    ... with facebook share with twitter share with linkedin Severe Combined Immunodeficiency (SCID) SCID is a group of rare disorders ... life-saving treatments. Why Is the Study of Severe Combined Immunodeficiency (SCID) a Priority for NIAID? SCID is a ...

  7. Birth control pills - combination

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000655.htm Birth control pills - combination To use the sharing features on ... both progestin and estrogen. What Are Combination Birth Control Pills? Birth control pills help keep you from ...

  8. A Survey of Alternative Oxygen Production Technologies

    Science.gov (United States)

    Lueck, Dale E.; Parrish, Clyde F.; Buttner, William J.; Surma, Jan M.; Delgado, H. (Technical Monitor)

    2001-01-01

    Utilization of the Martian atmosphere for the production of fuel and oxygen has been extensively studied. The baseline fuel production process is a Sabatier reactor, which produces methane and water from carbon dioxide and hydrogen. The oxygen produced from the electrolysis of the water is only half of that needed for methane-based rocket propellant, and additional oxygen is needed for breathing air, fuel cells and other energy sources. Zirconia electrolysis cells for the direct reduction of CO2 arc being developed as an alternative means of producing oxygen, but present many challenges for a large-scale oxygen production system. The very high operating temperatures and fragile nature of the cells coupled with fairly high operating voltages leave room for improvement. This paper will survey alternative oxygen production technologies, present data on operating characteristics, materials of construction, and some preliminary laboratory results on attempts to implement each. Our goal is to significantly improve upon the characteristics of proposed zirconia cells for oxygen production. To achieve that goal we are looking at electrolytic systems that operate at significantly lower temperatures, preferably below 31C to allow the incorporation of liquid CO2 in the electrolyte. Our preliminary results indicate that such a system will have much higher current densities and have simpler cathode construction than a porous gas feed electrode system. Such a system could be achieved based on nonaqueous electrolytes or ionic liquids. We are focusing our research on the anode reaction that will produce oxygen from a product generated at the cathode using CO2 as the feed. Operation at low temperatures also will open up the full range of polymer and metal materials, allowing a more robust system design to withstand the rigors of flight, landing, and long term unattended operation on the surface of Mars.

  9. Oxygen tension affects lubricin expression in chondrocytes.

    Science.gov (United States)

    Hatta, Taku; Kishimoto, Koshi N; Okuno, Hiroshi; Itoi, Eiji

    2014-10-01

    We assessed the effects of oxygen tension on lubricin expression in bovine chondrocytes and cartilage explants and a role for hypoxia-inducible transcription factor (HIF)-1α in regulating lubricin expression was investigated using a murine chondroprogenitor cell line, ATDC5, and bovine chondrocytes isolated from superficial and middle/deep zones of femoral cartilage. ATDC5 cells and bovine chondrocytes were cultured in micromass under different oxygen tensions (21%, 5%, and 1%). ATDC5 cells and middle/deep zone chondrocytes that initially had low lubricin expression levels were also cultured with or without transforming growth factor (TGF)-β1. Quantitative reverse transcription (RT)-PCR was used to determine lubricin and chondrogenic marker gene mRNA levels and immunohistochemistry was used to assess lubricin protein expression. Explant cartilage plugs cultured under different oxygen tensions were also subjected to immunohistological analysis for lubricin. HIF-1α gene silencing was achieved by electroporatic transfer into ATDC5 cells. A low oxygen tension reduced lubricin gene expression levels in bovine superficial chondrocytes, TGF-β1-treated middle/deep zone chondrocytes, and TGF-β1-treated ATDC5 cells. Lubricin expression in explant cartilage was also suppressed under hypoxia. HIF-1α gene silencing in ATDC5 cells attenuated the lubricin expression response to the oxygen tension. These results corroborate with previous studies that the oxygen tension regulates lubricin gene expression and suggest that HIF-1α plays an important role in this regulation. The normal distribution of lubricin in articular cartilage may be due to the hypoxic oxygen environment of cartilage as it is an avascular tissue. An oxygen tension gradient may be a key factor for engineering cartilage tissue with a layered morphology.

  10. Oxygen dependency of germinating Brassica seeds

    Science.gov (United States)

    Park, Myoung Ryoul; Hasenstein, Karl H.

    2016-02-01

    Establishing plants in space, Moon or Mars requires adaptation to altered conditions, including reduced pressure and composition of atmospheres. To determine the oxygen requirements for seed germination, we imbibed Brassica rapa seeds under varying oxygen concentrations and profiled the transcription patterns of genes related to early metabolism such as starch degradation, glycolysis, and fermentation. We also analyzed the activity of lactate dehydrogenase (LDH) and alcohol dehydrogenase (ADH), and measured starch degradation. Partial oxygen pressure (pO2) greater than 10% resulted in normal germination (i.e., protrusion of radicle about 18 hours after imbibition) but lower pO2 delayed and reduced germination. Imbibition in an oxygen-free atmosphere for three days resulted in no germination but subsequent transfer to air initiated germination in 75% of the seeds and the root growth rate was transiently greater than in roots germinated under ambient pO2. In hypoxic seeds soluble sugars degraded faster but the content of starch after 24 h was higher than at ambient oxygen. Transcription of genes related to starch degradation, α-amylase (AMY) and Sucrose Synthase (SUS), was higher under ambient O2 than under hypoxia. Glycolysis and fermentation pathway-related genes, glucose phosphate isomerase (GPI), 6-phosphofructokinase (PFK), fructose 1,6-bisphosphate aldolase (ALD), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), pyruvate decarboxylase (PDC), LDH, and ADH, were induced by low pO2. The activity of LDH and ADH was the highest in anoxic seeds. Germination under low O2 conditions initiated ethanolic fermentation. Therefore, sufficient oxygen availability is important for germination before photosynthesis provides necessary oxygen and the determination of an oxygen carrying capacity is important for uniform growth in space conditions.

  11. Cyanobacterial diazotrophy and Earth's delayed oxygenation

    Directory of Open Access Journals (Sweden)

    Stephanie L Olson

    2016-09-01

    Full Text Available The redox landscape of Earth’s ocean-atmosphere system has changed dramatically throughout Earth history. Although Earth’s protracted oxygenation is undoubtedly the consequence of cyanobacterial oxygenic photosynthesis, the relationship between biological O2 production and Earth’s redox evolution remains poorly understood. Existing models for Earth’s oxygenation cannot adequately explain the nearly 2.5 billion year delay between the origin of oxygenic photosynthesis and the oxygenation of the deep ocean, in large part owing to major deficiencies in our understanding of the coevolution of O2 and Earth’s key biogeochemical cycles (e.g., the N cycle. For example, although possible links between O2 and N scarcity have been previously explored, the consequences of N2 limitation for net biological O2 production have not been examined thoroughly. Here, we revisit the prevailing view that N2 fixation has always been able to keep pace with P supply and discuss the possibility that bioavailable N, rather than P, limited export production for extended periods of Earth’s history. Based on the observation that diazotrophy occurs at the expense of oxygenesis in the modern ocean, we suggest that an N-limited biosphere may be inherently less oxygenic than a P-limited biosphere—and that cyanobacterial diazotrophy was a primary control on the timing and tempo of Earth’s oxygenation by modulating net biogenic O2 fluxes. We further hypothesize that negative feedbacks inhibit the transition between N and P limitation, with the implication that the pervasive accumulation of O2 in Earth’s ocean-atmosphere system may not have been an inevitable consequence of oxygenic photosynthesis by marine cyanobacteria.

  12. The origin and evolution of oxygenic photosynthesis

    Science.gov (United States)

    Blankenship, R. E.; Hartman, H.

    1998-01-01

    The evolutionary developments that led to the ability of photosynthetic organisms to oxidize water to molecular oxygen are discussed. Two major changes from a more primitive non-oxygen-evolving reaction center are required: a charge-accumulating system and a reaction center pigment with a greater oxidizing potential. Intermediate stages are proposed in which hydrogen peroxide was oxidized by the reaction center, and an intermediate pigment, similar to chlorophyll d, was present.

  13. Clinical review: Oxygen as a signaling molecule

    OpenAIRE

    2010-01-01

    Molecular oxygen is obviously essential for conserving energy in a form useable for aerobic life; however, its utilization comes at a cost - the production of reactive oxygen species (ROS). ROS can be highly damaging to a range of biological macromolecules, and in the past the overproduction of these short-lived molecules in a variety of disease states was thought to be exclusively toxic to cells and tissues such as the lung. Recent basic research, however, has indicated that ROS production -...

  14. Phosphorous–vacancy–oxygen defects in silicon

    KAUST Repository

    Wang, Hao

    2013-07-30

    Electronic structure calculations employing the hybrid functional approach are used to gain fundamental insight in the interaction of phosphorous with oxygen interstitials and vacancies in silicon. It recently has been proposed, based on a binding energy analysis, that phosphorous–vacancy–oxygen defects may form. In the present study we investigate the stability of this defect as a function of the Fermi energy for the possible charge states. Spin polarization is found to be essential for the charge neutral defect.

  15. Rosacea, Reactive Oxygen Species, and Azelaic Acid

    OpenAIRE

    David A. Jones

    2009-01-01

    Rosacea is a common skin condition thought to be primarily an inflammatory disorder. Neutrophils, in particular, have been implicated in the inflammation associated with rosacea and mediate many of their effects through the release of reactive oxygen species. Recently, the role of reactive oxygen species in the pathophysiology of rosacea has been recognized. Many effective agents for rosacea, including topical azelaic acid and topical metronidazole, have anti-inflammatory properties. in-vitro...

  16. COMBINE 2 seminar

    DEFF Research Database (Denmark)

    Sørensen, Lars Schiøtt; Jacobsen, Kim

    1995-01-01

    A seminar about the COMBINE project was described. Further, the project was described in generel, i.e. the COMBINE´s data model (IDM), the data exchange system (DES) and the different I/O-systems included in COMBINE 2......A seminar about the COMBINE project was described. Further, the project was described in generel, i.e. the COMBINE´s data model (IDM), the data exchange system (DES) and the different I/O-systems included in COMBINE 2...

  17. Atmospheric oxygenation three billion years ago.

    Science.gov (United States)

    Crowe, Sean A; Døssing, Lasse N; Beukes, Nicolas J; Bau, Michael; Kruger, Stephanus J; Frei, Robert; Canfield, Donald E

    2013-09-26

    It is widely assumed that atmospheric oxygen concentrations remained persistently low (less than 10(-5) times present levels) for about the first 2 billion years of Earth's history. The first long-term oxygenation of the atmosphere is thought to have taken place around 2.3 billion years ago, during the Great Oxidation Event. Geochemical indications of transient atmospheric oxygenation, however, date back to 2.6-2.7 billion years ago. Here we examine the distribution of chromium isotopes and redox-sensitive metals in the approximately 3-billion-year-old Nsuze palaeosol and in the near-contemporaneous Ijzermyn iron formation from the Pongola Supergroup, South Africa. We find extensive mobilization of redox-sensitive elements through oxidative weathering. Furthermore, using our data we compute a best minimum estimate for atmospheric oxygen concentrations at that time of 3 × 10(-4) times present levels. Overall, our findings suggest that there were appreciable levels of atmospheric oxygen about 3 billion years ago, more than 600 million years before the Great Oxidation Event and some 300-400 million years earlier than previous indications for Earth surface oxygenation.

  18. Controlled supplemental oxygenation during tracheobronchial hygiene.

    Science.gov (United States)

    Walsh, C M; Bada, H S; Korones, S B; Carter, M A; Wong, S P; Arheart, K

    1987-01-01

    The effect of controlled supplemental oxygenation without bag ventilation on transcutaneous partial pressure of oxygen (TcPO2) measurements during tracheobronchial hygiene was evaluated. Procedure A, no supplemental oxygenation, was compared to Procedure B, in which controlled supplemental oxygenation was used. For controlled supplemental oxygenation, the FiO2 was increased until TcPO2 measurements rose to levels between 90 and 100 torr. Sixteen premature infants who required mechanical ventilation were studied in the neonatal center. Both procedures were performed on each patient in random order. In both procedures, a precipitous decrease in TcPO2 was observed during chest vibration, and further decrease in TcPO2 was noted with endotracheal suctioning. Except for baseline readings, throughout the tracheobronchial hygiene TcPO2 measurements were significantly higher and more subjects maintained TcPO2 values greater than 40 torr in Procedure B. In Procedure A corresponding TcPO2 measurements were 40 torr or less. Mean recovery time was shorter in Procedure B, 2.1 +/- 2.3 minutes, than in Procedure A, 4.9 +/- 2.8 minutes, p less than .003. Thus, in most patients, controlled supplemental oxygenation without manual bag ventilation seems sufficient to prevent hypoxia during tracheobronchial hygiene; it also shortens recovery time from hypoxemia as a result of the bronchopulmonary hygiene procedure.

  19. EUV measurement of ionospheric oxygen ions

    Science.gov (United States)

    Nakasaka, Y.; Yamazaki, A.; Yoshikawa, I.; Tashiro, S.; Miyake, W.; Nakamura, M.

    2001-12-01

    We have measured the OII emission from the F-layer ionosphere by the sounding rocket SS-520-2, which was launched from the Svalbard Rocket Experiment Site, Ny Aalesund in Norway, last December. This was the first in situ EUV observation of the ionospheric Oxygen ions. Oxygen ion is the main component of the ionospheric F layer. We have studied the oxygen ions distribution in the ionosphere by means of optical observation. Oxygen ions resonantly scatter the solar OII(83.4nm) line. We have built an extreme ultraviolet (XUV) scanner, which is sensitive to the OII 83.4-nm emission and contamination free from the Lyman-alpha line, especially for the sounding rocket SS-520-2. The rocket flew along the magnetospheric cusp region, and 600 sec after the launch it reached its apex at 1108 km in altitude, and its total operation time was 1100sec. In the downleg of the flight, below 350 km in altitude (900-1100sec after the launch), XUV observed very high intensity (200~300 Rayleigh) of OII emissions from the ionospheric F layer. We have estimated the column density of the oxygen ion along the XUV_fs line-of-sight from the measured OII intensity. In this presentation, we will discuss the density profile of the oxygen ions in the ionospheric F region, i.e., the dependence on the altitude, longitude and latitude. We will compare the obtained distribution with the model of the ionosphere.

  20. The jumbo squid, Dosidicus gigas (Ommastrephidae), living in oxygen minimum zones II: Blood-oxygen binding

    Science.gov (United States)

    Seibel, Brad A.

    2013-10-01

    Dosidicus gigas is a large, metabolically active squid that migrates across a strong oxygen and temperature gradient in the Eastern Pacific. Here we analyze the oxygen-binding properties of the squid's respiratory protein (hemocyanin, Hc) that facilitate such activity. A high Hc-oxygen affinity, strong temperature dependence, and pronounced pH sensitivity (P50=0.009T2.03, pH 7.4; Bohr coefficient=ΔlogP50/ΔpH=-1.55+0.034T) of oxygen binding facilitate night-time foraging in the upper water column, and support suppressed oxygen demand in hypoxic waters at greater depths. Expanding hypoxia may act to alter the species habitable depth range. This analysis supports the contention that ocean acidification could limit oxygen carrying capacity in squids at warmer temperature leading to reduced activity levels or altered distribution.

  1. Pulsations of massive ZZ Ceti stars with carbon/oxygen and oxygen/neon cores

    CERN Document Server

    Corsico, A H; Althaus, L G; Isern, J

    2004-01-01

    We explore the adiabatic pulsational properties of massive white dwarf stars with hydrogen-rich envelopes and oxygen/neon and carbon/oxygen cores. To this end, we compute the cooling of massive white dwarf models for both core compositions taking into account the evolutionary history of the progenitor stars and the chemical evolution caused by time-dependent element diffusion. In particular, for the oxygen/neon models, we adopt the chemical profile resulting from repeated carbon-burning shell flashes expected in very massive white dwarf progenitors. For carbon/oxygen white dwarfs we consider the chemical profiles resulting from phase separation upon crystallization. For both compositions we also take into account the effects of crystallization on the oscillation eigenmodes. We find that the pulsational properties of oxygen/neon white dwarfs are notably different from those made of carbon/oxygen, thus making asteroseismological techniques a promising way to distinguish between both types of stars and, hence, t...

  2. Simulation of blood oxygenation in capillary membrane oxygenators using modified sulfite solution.

    Science.gov (United States)

    Tabesh, Hadi; Amoabediny, Ghasem; Rasouli, Ali; Ramedani, Arash; Poorkhalil, Ali; Kashefi, Ali; Mottaghy, Khosrow

    2014-12-01

    Blood oxygenation is the main performance characteristic of capillary membrane oxygenators (CMOs). Handling of natural blood in in vitro investigations of CMOs is quite complex and time-consuming. Since the conventional blood analog fluids (e.g. water/glycerol) lack a substance with an affinity to capture oxygen comparable to hemoglobin's affinity, in this study a novel approach using modified sulfite solution is proposed to address this challenge. The solution comprises sodium sulfite as a component, simulating the role of hemoglobin in blood oxygenation. This approach is validated by OTR (oxygen transfer rate) measured using native porcine blood, in two types of commercially available CMOs. Consequently, the number of complicated natural blood investigations in the evolution procedure of newly developed oxygenators would considerably decrease. Moreover, the reassessing of failed devices, in clinics, would be performed more precisely using a modified sulfite solution than simple water/glycerol testing.

  3. Ceramic oxygen transport membrane array reactor and reforming method

    Science.gov (United States)

    Kelly, Sean M.; Christie, Gervase Maxwell; Robinson, Charles; Wilson, Jamie R.; Gonzalez, Javier E.; Doraswami, Uttam R.

    2016-11-08

    The invention relates to a commercially viable modular ceramic oxygen transport membrane reforming reactor configured using repeating assemblies of oxygen transport membrane tubes and catalytic reforming reactors.

  4. OXYGEN ENHANCED COMBUSTION FOR NOx CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence E. Bool; Jack C. Chen; David R. Thompson

    2000-07-01

    Increased environmental regulations will require utility boilers to reduce NO{sub x} emissions to less than 0.15lb/MMBtu in the near term. Conventional technologies such as Selective Catalytic Reduction (SCR) and Selective Non-Catalytic Reduction (SNCR) are unable to achieve these lowered emission levels without substantially higher costs and major operating problems. Oxygen enhanced combustion is a novel technology that allows utilities to meet the NO{sub x} emission requirements without the operational problems that occur with SCR and SNCR. Furthermore, oxygen enhanced combustion can achieve these NO{sub x} limits at costs lower than conventional technologies. The objective of this program is to demonstrate the use of oxygen enhanced combustion as a technical and economical method of meeting the EPA State Implementation Plan for NO{sub x} reduction to less than 0.15lb/MMBtu for a wide range of boilers and coal. The oxygen enhanced coal combustion program (Task 1) focused this quarter on the specific objective of exploration of the impact of oxygen enrichment on NO{sub x} formation utilizing small-scale combustors for parametric testing. Research efforts toward understanding any limitations to the applicability of the technology to different burners and fuels such as different types of coal are underway. The objective of the oxygen transport membrane (OTM) materials development program (Task 2.1) is to ascertain a suitable material composition that can be fabricated into dense tubes capable of producing the target oxygen flux under the operating conditions. This requires that the material have sufficient oxygen permeation resulting from high oxygen ion conductivity, high electronic conductivity and high oxygen surface exchange rate. The OTM element development program (Task 2.2) objective is to develop, fabricate and characterize OTM elements for laboratory and pilot reactors utilizing quality control parameters to ensure reproducibility and superior performance

  5. Interfacial oxygen migration and its effect on the magnetic anisotropy in Pt/Co/MgO/Pt films

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xi; Feng, Chun, E-mail: fengchun@ustb.edu.cn, E-mail: ghyu@mater.ustb.edu.cn; Liu, Yang; Jiang, Shaolong; Hua Li, Ming; Hua Yu, Guang, E-mail: fengchun@ustb.edu.cn, E-mail: ghyu@mater.ustb.edu.cn [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China); Long Wu, Zheng [Analytical and Testing Center, Beijing Normal University, Beijing 100875 (China); Yang, Feng [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China)

    2014-02-03

    This paper reports the interfacial oxygen migration effect and its induced magnetic anisotropy evolution in Pt/Co/MgO/Pt films. During depositing the MgO layer, oxygen atoms from the MgO combine with the neighboring Co atoms, leading to the formation of CoO at the Co/MgO interface. Meanwhile, the films show in-plane magnetic anisotropy (IMA). After annealing, most of the oxygen atoms in CoO migrate back to the MgO layer, resulting in obvious improvement of Co/MgO interface and the enhancement of effective Co-O orbital hybridization. These favor the evolution of magnetic anisotropy from IMA to perpendicular magnetic anisotropy (PMA). The oxygen migration effect is achieved by the redox reaction at the Co/MgO interface. On the contrary, the transfer from IMA to PMA cannot be observed in Pt/Co/Pt films due to the lack of interfacial oxygen migration.

  6. Microsensor and transcriptomic signatures of oxygen depletion in biofilms associated with chronic wounds: Biofilms and oxygen

    Energy Technology Data Exchange (ETDEWEB)

    James, Garth A. [Center for Biofilm Engineering, Montana State University, Bozeman Montana; Ge Zhao, Alice [Division of Dermatology, Department of Medicine, University of Washington, Seattle Washington; Usui, Marcia [Division of Dermatology, Department of Medicine, University of Washington, Seattle Washington; Underwood, Robert A. [Division of Dermatology, Department of Medicine, University of Washington, Seattle Washington; Nguyen, Hung [The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman Washington; Beyenal, Haluk [The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman Washington; deLancey Pulcini, Elinor [Center for Biofilm Engineering, Montana State University, Bozeman Montana; Agostinho Hunt, Alessandra [Department of Microbiology and Molecular Genetics, 5180 Biomedical and Physical Sciences, Michigan State University, East Lansing Michigan; Bernstein, Hans C. [Pacific Northwest National Laboratory, Chemical and Biological Signature Science, Richland Washington; Fleckman, Philip [Division of Dermatology, Department of Medicine, University of Washington, Seattle Washington; Olerud, John [Division of Dermatology, Department of Medicine, University of Washington, Seattle Washington; Williamson, Kerry S. [Center for Biofilm Engineering, Montana State University, Bozeman Montana; Franklin, Michael J. [Center for Biofilm Engineering, Montana State University, Bozeman Montana; Stewart, Philip S. [Center for Biofilm Engineering, Montana State University, Bozeman Montana

    2016-02-16

    Polymicrobial biofilms have been implicated in delayed wound healing, although the mechanisms by which biofilms impair wound healing are poorly understood. Many species of bacteria produce exotoxins and exoenzymes that may inhibit healing. In addition, oxygen consumption by biofilms may impede wound healing. In this study, we used oxygen microsensors to measure oxygen transects through in vitro-cultured biofilms, biofilms formed in vivo in a diabetic (db/db) mouse model, and ex vivo human chronic wound specimens. The results show that oxygen levels within both euthanized and live mouse wounds had steep gradients that reached minima ranging from 19 to 61% oxygen partial pressure, compared to atmospheric oxygen levels. The oxygen gradients in the mouse wounds were similar to those observed for clinical isolates cultured in vitro and for human ex vivo scabs. No oxygen gradients were observed for heat-killed scabs, suggesting that active metabolism by the viable bacteria contributed to the reduced oxygen partial pressure of the wounds. To characterize the metabolic activities of the bacteria in the mouse wounds, we performed transcriptomics analyses of Pseudomonas aeruginosa biofilms associated with the db/db mice wounds using Affymetrix microarrays. The results demonstrated that the bacteria expressed genes for metabolic activities associated with cell growth. Interestingly, the transcriptome results indicated that the bacteria within the wounds also experienced oxygen-limitation stress. Among the bacterial genes that were expressed in vivo were genes associated with the Anr-mediated hypoxia-stress response. Other bacterial stress response genes highly expressed in vivo were genes associated with stationary-phase growth, osmotic stress, and RpoH-mediated heat shock stress. Overall, the results support the hypothesis that the metabolic activities of bacteria in biofilms act as oxygen sinks in chronic wounds and that the depletion of oxygen contributes to the

  7. Evaluation of Oxygen Concentrators and Chemical Oxygen Generators at Altitude and Temperature Extremes

    Science.gov (United States)

    2015-04-22

    producing similar results. Oxygen concentrators have also shown to be an effective and economical substitute for compressed oxygen cylinders in remote high... Fischer et al. [10] conducted a study in an altitude chamber with volunteers having chronic obstructive pulmonary disease using five commercially...interest in employing this technology in areas where providing oxygen in cylinders or in liquid form is logistically difficult or economically

  8. Retinal Vessel Oxygen Saturation during 100% Oxygen Breathing in Healthy Individuals.

    Directory of Open Access Journals (Sweden)

    Olof Birna Olafsdottir

    Full Text Available To detect how systemic hyperoxia affects oxygen saturation in retinal arterioles and venules in healthy individuals.Retinal vessel oxygen saturation was measured in 30 healthy individuals with a spectrophotometric retinal oximeter (Oxymap T1. Oximetry was performed during breathing of room air, 100% oxygen (10 minutes, 6L/min and then again room air (10 minutes recovery.Mean oxygen saturation rises modestly in retinal arterioles during 100% oxygen breathing (94.5%±3.8 vs. 92.0%±3.7% at baseline, p<0.0001 and dramatically in retinal venules (76.2%±8.0% vs. 51.3%±5.6%, p<0.0001. The arteriovenous difference decreased during 100% oxygen breathing (18.3%±9.0% vs. 40.7%±5.7%, p<0.0001. The mean diameter of arterioles decreased during 100% oxygen breathing compared to baseline (9.7±1.4 pixels vs. 10.3±1.3 pixels, p<0.0001 and the same applies to the mean venular diameter (11.4±1.2 pixels vs. 13.3±1.5 pixels, p<0.0001.Breathing 100% oxygen increases oxygen saturation in retinal arterioles and more so in venules and constricts them compared to baseline levels. The dramatic increase in oxygen saturation in venules reflects oxygen flow from the choroid and the unusual vascular anatomy and oxygen physiology of the eye.

  9. Direct observation of the oxygenated species during oxygen reduction on a platinum fuel cell cathode

    OpenAIRE

    Kaya, Sarp; Casalongue, Hernan Sanchez; Viswanathan, Venkatasubramanian ; Miller, Daniel J. ; Friebel, Daniel ; Hansen, Heine A. ; Nørskov, Jens K. ; Nilsson, Anders ; Ogasawara, Hirohito

    2013-01-01

    The performance of polymer electrolyte membrane fuel cells is limited by the reduction at the cathode of various oxygenated intermediates in the four-electron pathway of the oxygen reduction reaction. Here we use ambient pressure X-ray photoelectron spectroscopy, and directly probe the correlation between the adsorbed species on the surface and the electrochemical potential. We demonstrate that, during the oxygen reduction reaction, hydroxyl intermediates on the cathode surface occur in sever...

  10. Gasification combined cycle power generation - process alternatives

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E.; Korhonen, M.

    1988-01-01

    Interest in Integrated Gasification Combined Cycle (IGCC) power plants has recently increased also in Finland. The IGCC systems offer the potential of superior efficiency and environmental performance over conventional pulverized coal or peat fired boilers. Potential applications are both large-scale electricity production from coal and medium-scale combined heat and electricity production. In the latter case, the gasification process should also be applicable to peat and wood. Several IGCC processes have been developed in USA and in Europe. These processes differ from each other in many respects. Nearest to commercialization are processes, which employ oxygen gasification and cold gas cleanup. The Cool Water plant, which was brought into operation in 1984 in USA, has demonstrated the feasibility of an IGCC system using Texaco entrained-bed gasifier. Several pressurized fluidized-bed and fixed-bed gasification processes have also reached a pilot or demonstration stage with a wide variety of coals from lignite to hard coal. Pressurized fluidized-bed gasification of peat (Rheinbraun-HTW-process) will also be demonstrated at the peat ammonia plant of Kemira Oy, which will be commissioned in 1988 in Oulu, Finland. Oxygen gasification and cold gas cleanup are, however, economically viable only in large-scale applications. Technology is being developed to simplify the IGCC system, in order to reduce its capital costs and increase its efficiency. Air gasification combined with ho gas cleanup seems to have a great potential of improving the competitiveness of the IGCC system.

  11. Subpicosecond oxygen trapping in the heme pocket of the oxygen sensor FixL observed by time-resolved resonance Raman spectroscopy.

    Science.gov (United States)

    Kruglik, Sergei G; Jasaitis, Audrius; Hola, Klara; Yamashita, Taku; Liebl, Ursula; Martin, Jean-Louis; Vos, Marten H

    2007-05-01

    Dissociation of oxygen from the heme domain of the bacterial oxygen sensor protein FixL constitutes the first step in hypoxia-induced signaling. In the present study, the photodissociation of the heme-O2 bond was used to synchronize this event, and time-resolved resonance Raman (TR(3)) spectroscopy with subpicosecond time resolution was implemented to characterize the heme configuration of the primary photoproduct. TR(3) measurements on heme-oxycomplexes are highly challenging and have not yet been reported. Whereas in all other known six-coordinated heme protein complexes with diatomic ligands, including the oxymyoglobin reported here, heme iron out-of-plane motion (doming) occurs faster than 1 ps after iron-ligand bond breaking; surprisingly, no sizeable doming is observed in the oxycomplex of the Bradyrhizobium japonicum FixL sensor domain (FixLH). This assessment is deduced from the absence of the iron-histidine band around 217 cm(-1) as early as 0.5 ps. We suggest that efficient ultrafast oxygen rebinding to the heme occurs on the femtosecond time scale, thus hindering heme doming. Comparing WT oxy-FixLH, mutant proteins FixLH-R220H and FixLH-R220Q, the respective carbonmonoxy-complexes, and oxymyoglobin, we show that a hydrogen bond of the terminal oxygen atom with the residue in position 220 is responsible for the observed behavior; in WT FixL this residue is arginine, crucially implicated in signal transmission. We propose that the rigid O2 configuration imposed by this residue, in combination with the hydrophobic and constrained properties of the distal cavity, keep dissociated oxygen in place. These results uncover the origin of the "oxygen cage" properties of this oxygen sensor protein.

  12. Metal ferrite oxygen carriers for chemical looping combustion of solid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Siriwardane, Ranjani V.; Fan, Yueying

    2017-01-31

    The disclosure provides a metal ferrite oxygen carrier for the chemical looping combustion of solid carbonaceous fuels, such as coal, coke, coal and biomass char, and the like. The metal ferrite oxygen carrier comprises MFe.sub.xO.sub.y on an inert support, where MFe.sub.xO.sub.y is a chemical composition and M is one of Mg, Ca, Sr, Ba, Co, Mn, and combinations thereof. For example, MFe.sub.xO.sub.y may be one of MgFe.sub.2O.sub.4, CaFe.sub.2O.sub.4, SrFe.sub.2O.sub.4, BaFe.sub.2O.sub.4, CoFe.sub.2O.sub.4, MnFeO.sub.3, and combinations thereof. The MFe.sub.xO.sub.y is supported on an inert support. The inert support disperses the MFe.sub.xO.sub.y oxides to avoid agglomeration and improve performance stability. In an embodiment, the inert support comprises from about 5 wt. % to about 60 wt. % of the metal ferrite oxygen carrier and the MFe.sub.xO.sub.y comprises at least 30 wt. % of the metal ferrite oxygen carrier. The metal ferrite oxygen carriers disclosed display improved reduction rates over Fe.sub.2O.sub.3, and improved oxidation rates over CuO.

  13. Oxygenation-sensitive CMR for assessing vasodilator-induced changes of myocardial oxygenation

    Directory of Open Access Journals (Sweden)

    Wang Jiun

    2010-03-01

    Full Text Available Abstract Background As myocardial oxygenation may serve as a marker for ischemia and microvascular dysfunction, it could be clinically useful to have a non-invasive measure of changes in myocardial oxygenation. However, the impact of induced blood flow changes on oxygenation is not well understood. We used oxygenation-sensitive CMR to assess the relations between myocardial oxygenation and coronary sinus blood oxygen saturation (SvO2 and coronary blood flow in a dog model in which hyperemia was induced by intracoronary administration of vasodilators. Results During administration of acetylcholine and adenosine, CMR signal intensity correlated linearly with simultaneously measured SvO2 (r2 = 0.74, P 2 and CMR signal intensity were exponentially related to coronary blood flow, with SvO2 approaching 87%. Conclusions Myocardial oxygenation as assessed with oxygenation-sensitive CMR imaging is linearly related to SvO2 and is exponentially related to vasodilator-induced increases of blood flow. Oxygenation-sensitive CMR may be useful to assess ischemia and microvascular function in patients. Its clinical utility should be evaluated.

  14. Selective Oxidation of Light Hydrocarbons Using Lattice Oxygen Instead of Molecular Oxygen

    Institute of Scientific and Technical Information of China (English)

    沈师孔; 李然家; 周吉萍; 余长春

    2003-01-01

    In this paper, selective oxidation of n-butane to maleic anhydride (MA) and partial oxidation of methane to synthesis gas with lattice oxygen instead of molecular oxygen are investigated. For the oxidation of butane to MA in the absence of molecular oxygen, the Ce-Fe promoted VPO catalyst has more available lattice oxygen and provides higher conversion and selectivity than that of the unpromoted one. It is supposed that the introduction of Ce-Fe complex oxides improves redox performance of VPO catalyst and increases the activity of lattice oxygen.For partial oxidation of methane to synthesis gas over LaFeO3 and Lao.8Sro.gFeO3 oxides, the reaction with flow switched between 11% O2-Ar and 11% CH4-He at 900℃ was carried out. The results show that methane can be oxidized to CO and H2 with selectivity over 93% by the lattice oxygen of the catalyst in an appropriate reaction condition, while the lost lattice oxygen can be supplemented by air re-oxidation. It is viable for the lattice oxygen of the LaFeO3 and La0.8Sr0.2FeO3 catalyst instead of molecular oxygen to react with methane to synthesis gas in the redox mode.

  15. Comparative quantification of oxygen release by wetland plants: electrode technique and oxygen consumption model.

    Science.gov (United States)

    Wu, Haiming; Liu, Jufeng; Zhang, Jian; Li, Cong; Fan, Jinlin; Xu, Xiaoli

    2014-01-01

    Understanding oxygen release by plants is important to the design of constructed wetlands for wastewater treatment. Lab-scale systems planted with Phragmites australis were studied to evaluate the amount of oxygen release by plants using electrode techniques and oxygen consumption model. Oxygen release rate (0.14 g O2/m(2)/day) measured using electrode techniques was much lower than that (3.94-25.20 gO2/m(2)/day) calculated using the oxygen consumption model. The results revealed that oxygen release by plants was significantly influenced by the oxygen demand for the degradation of pollutants, and the oxygen release rate increased with the rising of the concentration of degradable materials in the solution. The summary of the methods in qualifying oxygen release by wetland plants demonstrated that variations existed among different measuring methods and even in the same measuring approach. The results would be helpful for understanding the contribution of plants in constructed wetlands toward actual wastewater treatment.

  16. Oxygen generator for medical applications (USIC)

    Energy Technology Data Exchange (ETDEWEB)

    Staiger, C. L.

    2012-03-01

    The overall Project objective is to develop a portable, non-cryogenic oxygen generator capable of supplying medical grade oxygen at sufficient flow rates to allow the field application of the Topical Hyperbaric Oxygen Therapy (THOT{reg_sign}) developed by Numotech, Inc. This project was sponsored by the U.S. Department of Energy Global Initiatives for Proliferation Prevention (GIPP) and is managed by collaboration between Sandia National Laboratories (SNL), Numotech, Inc, and LLC SPE 'Spektr-Conversion.' The project had two phases, with the objective of Phase I being to develop, build and test a laboratory prototype of the membrane-pressure swing adsorber (PSA) system producing at 15 L/min of oxygen with a minimum of 98% oxygen purity. Phase II objectives were to further refine and identify the pre-requisites needed for a commercial product and to determine the feasibility of producing 15 L/min of oxygen with a minimum oxygen purity of 99%. In Phase I, Spektr built up the necessary infrastructure to perform experimental work and proceeded to build and demonstrate a membrane-PSA laboratory prototype capable of producing 98% purity oxygen at a flow rate of 5 L/min. Spektr offered a plausible path to scale up the process for 15 L/min. Based on the success and experimental results obtained in Phase I, Spektr performed work in three areas for Phase II: construction of a 15 L/min PSA; investigation of compressor requirements for the front end of the membrane/PSA system; and performing modeling and simulation of assess the feasibility of producing oxygen with a purity greater than 99%. Spektr successfully completed all of the tasks under Phase II. A prototype 15 L/min PSA was constructed and operated. Spektr determined that no 'off the shelf' air compressors met all of the specifications required for the membrane-PSA, so a custom compressor will likely need to be built. Modeling and simulation concluded that production of oxygen with purities greater

  17. Relationship between cerebral oxygen saturation and postoperative cognitive dysfunction in elderly patients under inhalational combined intravenous anesthesia%静吸复合麻醉下老年患者脑氧饱和度与术后认知功能变化之间的关系

    Institute of Scientific and Technical Information of China (English)

    贾宝森; 吴东宇; 张宏

    2005-01-01

    three groups rSO2 was significantly lower during operation (T4) and at the end of surgery (T5) than baseline (T0) (P<0.05). In all patients the MMSE scores at 1h after operation were significantly lower than the baseline value (P<0.05). The MMES scores in all patients significantly declined within 1-4h after surgery, and the cognitive function recovered at 4h after surgery in 85% patients. The critical values of rSO2 below which postoperative cognition dysfunction may occur were: 45 (group Ⅰ), 47 (group Ⅱ) and 49 (group Ⅲ) for isoflurane anesthesia subgroups;47 (group Ⅰ), 48 (group Ⅱ) and 50 (group Ⅲ) for sevoflurane subgroups. Conclusion The perioperative rSO2 should be maintained up to above 50% to reduce the incidence of postoperative cognitive dysfunction under inhalational combined intravenous anesthesia.

  18. Reporter cell activity within hydrogel constructs quantified from oxygen-independent bioluminescence.

    Science.gov (United States)

    Lambrechts, Dennis; Roeffaers, Maarten; Kerckhofs, Greet; Hofkens, Johan; Van de Putte, Tom; Schrooten, Jan; Van Oosterwyck, Hans

    2014-09-01

    By providing a three-dimensional (3D) support to cells, hydrogels offer a more relevant in vivo tissue-like environment as compared to two-dimensional cell cultures. Hydrogels can be applied as screening platforms to investigate in 3D the role of biochemical and biophysical cues on cell behaviour using bioluminescent reporter cells. Gradients in oxygen concentration that result from the interplay between molecular transport and cell metabolism can however cause substantial variability in the observed bioluminescent reporter cell activity. To assess the influence of these oxygen gradients on the emitted bioluminescence for various hydrogel geometries, a combined experimental and modelling approach was implemented. We show that the applied model is able to predict oxygen gradient independent bioluminescent intensities which correlate better to the experimentally determined viable cell numbers, as compared to the experimentally measured bioluminescent intensities. By analysis of the bioluminescence reaction dynamics we obtained a quantitative description of cellular oxygen metabolism within the hydrogel, which was validated by direct measurements of oxygen concentration within the hydrogel. Bioluminescence peak intensities can therefore be used as a quantitative measurement of reporter cell activity within a hydrogel, but an unambiguous interpretation of these intensities requires a compensation for the influence of cell-induced oxygen gradients on the luciferase activity.

  19. SR-Site: Oxygen ingress in the rock at Forsmark during a glacial cycle

    Energy Technology Data Exchange (ETDEWEB)

    Sidborn, Magnus (Kemakta Konsult AB (Sweden)); Sandstroem, Bjoern (WSP Sverige AB (Sweden)); Tullborg, Eva-Lena (Terralogica AB (Sweden)); Salas, Joaquin; Maia, Flavia; Delos, Anne; Molinero, Jorge (Amphos21 (Spain)); Hallbeck, Lotta; Pedersen, Karsten (Microbial Analytics Sweden AB (Sweden))

    2010-11-15

    The aim of this report is to assess the possibility for oxygen to be transported by glacial melt-water to canister positions in a final repository for spent nuclear fuel at the proposed location in Forsmark. The approach for this assessment is to combine reactive transport modelling with geological observations of present and historical indications of oxygen ingress. For safety assessment purposes a cautious approach in the modelling is required when estimating the extent of oxygen ingress. In this report, a cautious approach has been applied both in the conceptualisation of the problem and in the choice of input parameters used in the models. Oxygen consuming processes are only neglected in the modelling if they are expected to further decrease the extent of oxygen ingress. Several oxygen consuming processes have been identified, each of which may play an important role in the scavenging of oxygen along recharge flow paths in the rock. These processes include biological pathways with degradation of organic material of ground surface origin, and biotically mediated reactions with reduced rock minerals and with various materials expected to be present in the backfilled repository volume. In the absence of microbes most of these reactions may also follow abiotic pathways. Present day observations show that degradation of organic material is the most powerful oxygen scavenging process. At Forsmark, oxygen is generally depleted within a few metres under present day temperate conditions. Although biological activity is likely to exist also during different phases of a glaciation, large uncertainties exist regarding e.g. the population growth dynamics, the biotic reaction rates and the availability of organic material under the highly varying conditions expected. Microbial activity and degradation of organic material is therefore pessimistically neglected in the calculations in this report. In the absence of organic material, ferrous iron present in minerals in the rock

  20. Oxygen and carbon discovered in exoplanet atmosphere `blow-off'

    Science.gov (United States)

    2004-02-01

    the ‘blow-off’ effect observed by the team during their October and November 2003 observations with Hubble had never been seen before. In honour of such a distinguished catalogue this extraordinary extrasolar planet has provisionally been dubbed 'Osiris'. Osiris was the Egyptian god who lost part of his body - like H